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The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!
20

The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
thread71-376751: Secondary engine balance
Anyone seen the CMC Sytek Scotch Yoke Engine? Completely kills the imbalance problems that conventional direct couple conn rod types suffer from. Interesting how it resembles the Original reverse cam effect Bourke Engine invented by Russell Bourke back in the early 1930's!
But what about utilizing only half the scotch yoke and applying it to conventional inline 4 and 6 cylinder engines? I thought this up decades ago when I was first introduced by a friend to the Bourke Engine Documentary written by Lois Bourke back in the early 70's. Have wondered what the real world result would be for a very long time and due to lack of resources, have not yet been able to find out. Would be easy enough to simulate on today's super fact computers.
It is very easy to realize that this solves imbalance and piston side loading problems associated with conventonal conn rod setups due to lack of direct coupling of the conn' rod to the throw. This advantege is obvious to anyone who can see and think.
One of Russell's main goals was to cure all vibration problems inherrant in conventional engines.
Also, there is a free piston engine design called the Bourke Engine, invented by Russell Bourke back in the 1930's! Basically a dual 2 stroke cylinder design with pistons fixed to a ridged inline connecting rod through a scotch yoke mechanism that simply imparts power to the rotating mass as it is not directly coupled thereto. Sort of the mechanical version of passive agressive! ;)
Russell Bourke designed the worlds first HCCI engine without realizing it or at least without naming it correctly. His primary discovery and goal was to achieve clean cool environmentally friendly exhaust emissions via an inverted combustion process known in conventional terms as pre-ignition! He so acheived these goals in his design. His purpose was to do away with multiple parasitic power robbing parts and that's exactly what he achieved way back in the 1930's! It's still the worlds most efficient piston I/C engine ever too!
For free info - www.bourke-engine.com / www.projectbourke.com

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

All claimed advantages were debunked LONG ago.

And there is zero chance that this design has a higher thermal efficiency than a good modern piston engine, while not having downsides that the inventors never mention.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

A search of this forum for "Bourke" reveals quite a few past threads, some of which date back 15 years. If the concept has been known for that long, and nothing has happened by now, it's not going to. It's an easy search, I'm not going to bother linking to all of them.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

"1/4 pound of fuel per HP hour"
Can someone check my math?
That looks like about 47 gallons of diesel per KWHr.
I'm used to seeing consumption figures around 13 gallons per KWHr for gen-sets.
Thirsty.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

"Completely kills the imbalance problems that conventional direct couple conn rod types suffer from"
http://www.autospeed.com/cms/article.html?&tit...
Yeah, engines with balancer shafts do tend to have fewer imbalance problems. Gosh, this must be rocket science.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

waross, you've lost me. The best engines I know manage around 0.25 lb/bhp hr

https://en.wikipedia.org/wiki/Brake-specific_fuel_...

The reluctance of the enthusiasts to actually allow proper witnessed tests of the engines speaks volumes.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Thanks Greg I didn't think my numbers looked right.
I'll look for my mistake.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

The Bourke engine depends on reversing sliding bearings, and they are its Achilles heel. These bearings operate at high peak speed under heavy load with one of two minimum speed regions (where hydrodynamic lubrication ceases) occurring near TDC where pressure is high. These issues can be mitigated using linear roller bearings, but they add a lot of weight and thus increase materials stress in reciprocating assemblies. Furthermore, its obvious the connecting rod and bearing arrangement results in forces being asymmetric around the connecting rod axis and there *is* a crank arm, so the claim of "balance" eludes me. To the extent the engine exhibits balance, it's due to the arrangement of its pistons, not its characteristic Scotch Yoke mechanism. Finally, the claim "It's still the worlds most efficient piston I/C engine ever too!" is unsubstantiated and thus unwarranted.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

If it only ran maybe 100 rpms max it may work. RodRico sums it up nicely.
The most efficient piston IC engines are the large 2 stroke marine engines not the one of this thread. And the Op engine made by Fairbanks Morse likely is as good as the large marine engines as well. Note for those sliding bearings to come close to lasting there would need to be some sort of flexible hose or sliding tube to feed oil pressure to them, even if they were a roller system like some cnc machine tool linier roller bearings are. Opps I see Rod mentioned them first.
They look like a manufacturing nightmare, I don't think that system would be very compatible with the now common practice of all aluminum engine block/ head construction. Recip engine balance seems to be a non problem nowadays, in automotive applications. I am guessing that the reason we have not seen this design being used is because of the excessive wear that it would cause, and the high costs of machine work and materials needed to make them last. The old crank train we are all used to is very difficult to replace when it comes to reciprocating pistons, it is efficient and works great even into the 20K rpm range maybe even more.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
Hah! Sounds like a Piston Slapper Club chat group! :D
I know exactly how you feel!
I would love to see conclusive test results myself some day!
Like Russell Bourke say's in the Documentary "you have to throw out everything you know about conventional engine design to understand the Bourke Cycle!"
The Bourke Cycle is what I call an Inverted Combustion process. The entire combustion / thermal cracking process is 100% complete before the piston gains mechanical advantage over the throw and begins its downstroke with the resulting pressure charge which cools during expansion rather than a flame front pushing the piston downward! That should tell you everything you need to know with regard to why you need to re-think the process hence design!
See for yourselves gents'!
We also have access to the original Bourke 400 4 cylinder prototype discussed and shown along with the 30 and various configurations thereof as well as his low rpm high torque naturally quiet 4 cylinder radials! All are direct drive except for the 30 twin.
The 400 boasts over 200HP at 2000 RPM. Same low EGT's!
Peace!
It's free!
Enjoy!
http://www.bourke-engine.com/engine/video.htm

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I see spark plugs.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Hmmm... it seems the OP wasn't really asking a question but promoting a website where one can buy Bourke Engine paraphernalia. If anyone is interested, the primary item ("Bourke Engine Documentary by Lois Bourke") is also available on several free energy sites, so make sure to shop around for the best price. Completely unrelated but rather interesting is the dialog between GregLocock and someone attempting to spread the unsubstantiated claims regarding the Bourke Engine via Wikipedia. See https://en.wikipedia.org/wiki/Talk:Bourke_engine

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Whenever I hear terms like "mechanical advantage" and "pushing the piston downward" when describing an IC engine, I wonder whether the inventer uses PV diagrams or just relies on thought experiments.

Steve

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

We've had various enthusiasts pushing Bourke on eng-tips as well. Predictably absolutely nothing has been heard of them since. I'm not sure how much a dyno session at a calibrated dyno facility costs, I'd guess $800 for a day, which would be ample time to generate a bsfc map demonstrating the claimed wonderful economy of the Bourke engine. The fact that NONE of these blowhards has ever even demonstrated a running engine, never mind putting one on a third party dyno, is fairly telling.

So far as piston slappers goes, actually that was a job of mine once, solving piston slap, on real production engines.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

The tale of a "successful" test of the Bourke Engine by the men who inherited the engine from Russell Bourke himself. In the very last paragraphs of the tale, the "remarkable" results are revealed to be the product of an error in measuring horsepower. thumbsup
http://www.niquette.com/books/sophmag/bourke.htm

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

A flat-four arrangement of a Bourke engine requires a first-order counter-rotating balance shaft. A flat-four conventional engines (with the pistons moving in a "boxer" arrangement) does not. The first-order balance situation is the same as an inline-twin with a 180-degree crankshaft. I have an engine like that in one of my motorcycles ... it has a balance shaft.

A flat-six arrangement has the same first-order balance situation as a conventional inline-three. Again, it requires a counter-rotating balance shaft in order to run smoothly. A flat-six "boxer" does not.

For that matter, a flat-twin arrangement of a Bourke requires counter-rotating balance shaft(s). A BMW flat-twin motorcycle engine does not!

Yeah, the piston motion is sinusoidal. The higher-order vibration effects are irrelevant if the first-order vibration is bad.

So, the claimed solution to "imbalance problems" is a crock.

Now, for the combustion system.

Yes, with purely sinusoidal motion, the piston spends less time near TDC than a conventional engine with swinging con-rod does. So what? It fundamentally doesn't change anything. Alternate combustion systems can be used with a conventional crank-and-rod arrangement just as well (or just as badly). The slight change in motion profile isn't going to drastically change the combustion process and its resulting efficiency, and its resulting emissions. It just isn't.

I suppose there is a slight theoretical benefit of connecting the piston in the middle rather than at piston pins, to conduct heat out of the middle of the piston and to take the load right in the middle - shorter load path, shorter heat transfer path. But, this is splitting hairs.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
"The Bourke engine depends on reversing sliding bearings, and they are its Achilles heel."

W R O N G ! ! ! ! The CMC Sytek uses a slider and worka perfectly! The lubrication issues were fully addressed and solved. The Sytek engine was proven viable via thousands of hours under load on a fully outfitted dyno/emissions etc. test rig AND was also test run in a few different vehicles on the roads for 10's of thousands of miles and has been ready for mass production and consumption for years now.

It was blackballed by the Cartel's because it was just too darn efficient killing Bourke's dreams of seeing his engines in broad use across the world staving off the now polluted biosphere we suffer from that he envisioned way back in the early 1900's and set out to avoid through 'complete thermochemical combination of carbon and oxygen basically yielding air and water as it's exhaust products @ substantially lower egt's as a result thereof, which were evidently achieved in the Bourke Cycle! Hence the arrangement of parts and form of engine. The use of ported valving was practical due to ultra high combustion temps' which back then would melt poppet valves but with today's high temp' materials, the Bourke Cycle can also operate safely in an overhead valve configuration both 5 cycle 2 stroke and 4 cycle 4 stroke mode.

The Bourke engine utilizes what Russel Bourke called the Tripple Slipper Bearing. See animation: http://www.bourke-engine.com/ani As you will see, a 3 layer high speed rotary bearing that SPINS on it's own axis in the opposite direction while spinning on the crankthrow and rolling across the shoe faces of each connecting rod that is solidly coupled through the yoke plates yielding a 1 piece assembly.
Debunked? I don't think so, not if you know the differences between opinion, rumor, fact and fiction and of course what 'constitutes actual proof'!
Please witness accordingly....
Watch the video clips of the Bourke 30 001 production engine hand made by Russell Bourke, acquired by Bourke-Engine.Com on behalf of Roger Richard linked in this thread.
Roger's prototype 30 is also feature which he made from scratch for want of an actual Bourke 30, running the Bourke Cycle itself! The man is a genius mechnaic, machinist and engineer just like Russel Bourke was!

And, True, the Bourke Engine Documenary is available all over the place but none of the other products offered are or should be due to copyright protection.

Not saying nor has I ever claimed the Bourke Engine is the end all be all form of IC piston engines but it's a damn good step in the right direction any day and I am not aware of any engine in production that is anywhere near as efficient as it was! Please correct me of I am wrong for I am keenly aware that inventors are coming up with new innovations all the time, which is great!
GodSpeed!

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

The combustion system doesn't "know" the mechanics of what's moving the piston. The means of air, fuel, and ignition delivery into the cylinder don't care that the piston is being operated by a Scotch yoke rather than a connecting rod. It doesn't make any difference. The slight difference due to pure sinusoidal motion is splitting hairs.

As far as I can tell, the Sytek demonstration engine was a four-stroke, spark ignition, stoichiometric air/fuel charge, Otto cycle.

Carbureted (premixed-charge) piston-ported two-strokes have awful fuel consumption and emissions. END.

Direct-injection spark-ignition two-strokes are in production (with normal connecting rods) - see Bombardier/Rotax/Evinrude E-tec - and although they are considerably better for fuel consumption and emissions than carbureted (or, at least, premixed-charge) two-strokes, they still use spark plugs, they still need a catalyst in the exhaust system, and they are not capable of meeting current automotive emission standards. (They are used in applications not subject to those standards.)

The "detonation" cycle, a.k.a. HCCI, doesn't work outside of the laboratory.

The video of the Bourke engine that I saw somewhere on the internet, had spark plugs.

Spare me the hand-waving (in the above post). Show me the P-V diagram, show me the means of ignition, show me how it achieves reliable ignition at any combination of engine temperature, ambient temperature, and engine load. Show me how it's preventing premixed-charge from being trapped in crevice volumes (and I will fully grant that the two-piston arrangement may be capable of reducing, but not eliminating, the crevice volume above the top compression ring). Show me how it's preventing premixed-charge from being quenched (stopped from burning) adjacent to chamber walls that are inherently at a temperature lower than ignition temperature (by quite a bit). If you are also claiming that combustion goes all the way into the boundary layers and crevice volumes because the temperature in those places is kept high enough for ignition, show me how it's preventing pre-ignition.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Cryptoman,

As the one asserting the superiority of the Bourke Engine, it's incumbent on you to provide objective evidence, not on everyone else to prove it can't work. You arguably have more information than anyone, and promote a web site selling that information, yet you've produced no actual evidence. I note you've also conveniently skipped over discussing the fact that a simple error in measuring horsepower by the Bourke team has been identified that explains it's alleged performance better than any measured test results you've produced thus far.

I love how folks pushing free energy or super-efficient engines that never caught on always turn to conspiracy theories; "Big oil suppressed it!" How do you explain the very public interest in the Achates Engine, Liquid Piston, Mazda's Spark Assisted HCCI, or Infinity's VCR engine?

Unsubstantiated absurdity. I don't have time to argue mythology any further.

Rod

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Quote (Cryptoman)

Please correct me of I am wrong

Well... knowledgeable people in this thread are trying to explain why you're wrong, and you aren't listening.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

2
Found an interesting article describing a real-world independent test. http://acversailles.free.fr/documentation/08~Docum...

I'm not surprised by its findings.

"Too long, didn't read"?

Underwhelming, and did not live up to its claims - not even remotely close to doing so, when constructed as per original specifications.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

It is still too expensive to manufacture, and the wear rates will be high depending on materials chosen.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Oh noes, we'd better end this thread or the cartels will send their black helicopters to eliminate every trace of this sekrit invention.

Continuing Brian's balance theme, an 8 cylinder Bourke engine would be fine for primary balance, with no balancer shaft required.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

5
During the 1980’s, this writer conducted a test of a 30 cubic inch Vaux engine, (a replica of the 30 cubic inch Bourke design), actually constructed using much of the original Bourke tooling. The goal of the test was to attempt to reproduce Bourke’s rather remarkable claims of 76 BHP at 10,000 rpm with stated brake specific fuel consumption values around .25 lbm/ bhp-hr. The project was undertaken with an optimistic approach to verifying the performance figures and to understand the thermodynamic processes that would allow these high specific power outputs to be obtained with high thermal efficiency.

The engine was tested on a water brake dynamometer after careful preparation and thorough break in. The test results were very disappointing, with power outputs and fuel consumption measurements being nowhere near what Bourke originally claimed. After many hours of careful adjustments and repeated tests, the best power recorded was 8.9 BHP at 4000 rpm where specific fuel consumption was a horrific 1.48 lbm/bhp-hr! The unloaded (free) speed was 5000 rpm maximum, a far cry from the stated figures. An induction airflow measurement revealed that the engine’s delivery ratio (volumetric efficiency) was only slightly better than 40% at 4000 rpm, dropping off sharply at higher engine speeds. It was obvious that this engine’s air handling characteristics were very deficient. My findings were as follows:

1) There was no indication of any unusual combustion phenomena occurring. Various low octane fuels were run and spark timing was advanced and mixture leaned in order to induce the “Bourke Cycle”. The engine responded like any other two-stroke – there was audible detonation with no increase in power output.
2) Best spark timing was around 35 degrees BTDC…any further advancing reduced power output. Leaning the mixture (via an adjustable main jet carburetor) past MBT (mean best torque) resulted in reduced power output. Using a 50:50 mixture of 87 octane unleaded gasoline and diesel fuel did increase the detonation intensity with no increase in power output or improved fuel consumption. The engine actually performed best on high octane gasoline.
3) The cool exhaust gasses were determined to be caused by fuel mixture short-circuiting out the exhaust ports during the scavenging process. The scotch yoke configuration allows the scavenge pump compression ratio to be very high – Bourke made use of this feature to obtain a ratio of approximately 3:1 (conventional two-strokes are around 1.3 to 1.5:1). When the transfer ports open, the pressure ratio was above the critical (Po/P = .528) thus choked flow occurred during the initial portion of the scavenge phase. The effect was that transferring fuel mixture short circuited right over the top of the piston deflector and out the open exhaust ports, without properly scavenging the cylinder of exhaust residual. Such a process could never result in the low fuel specifics and low exhaust emissions that Bourke claimed.
4) Vibration of this engine was indeed severe. Bourke 100% rotationally balanced the crankshaft without incorporating a reciprocating balance factor, thus all reciprocating forces were unresolved. Later, my engine’s counterweighting was altered to incorporate a 50% reciprocating balance factor. This made for somewhat tolerable vibration, but still not acceptable for a production machine.
5) Shearing of driveline components, which Bourke touted as high power potential, was actually high cyclic torsional inputs into the drive system. Bourke claimed that running a flywheel on his engine was detrimental to performance. I found that a flywheel was an absolute necessity to keep the dynamometer coupling in one piece.
6) Bourke states that the scotch yoke allows for a longer piston dwell time at TDC, thereby inducing the hydrogen/oxygen combustion process. He also states that the inherent straight-line motion allows for better resistance to failure when operating under detonation. As combustion was found not to differ from a more conventional engine, these claims are without merit.
7) The poor air delivery ratio was the result of both restrictive cylinder porting and lack of any induction or exhaust tuning. Cylinders were of the cross-scavenged type with drilled inlet, transfer and exhaust ports. The design was very similar to outboard motor technology of 1930’s vintage.

Heat energy liberated in the combustion of hydrocarbon fuels is determined by classic bomb calorimeter experiments. Here a known mass of fuel is burned in the presence of pure oxygen in excess. Virtually all of the fuel is consumed, the reaction goes to full completion, and results are therefore highly consistent and repeatable. Flame rates in the combustion bomb are the same as those encountered in engine cylinders when detonation occurs, this being due to combustion occurring in a pure oxygen environment. The conclusion is that there is no scientific possibility that more energy can be extracted from a given hydrocarbon fuel than that determined in the aforementioned experiment. As heat and work are mutually convertible quantities (Joule’s law), and knowing the fuel consumed during a given test, the engine performance can be predicted and checked against the dynamometer results. For this test, agreement was verified and indicated that approximately 9 BHP was all that was attainable.

Knowing the work out at the crankshaft, assuming realistic operational efficiencies and combustion being complete at TDC, and knowing the physical geometry of the engine, one can quite accurately calculate the temperature of the exhaust gasses when the exhaust ports open using a polytropic expansion relation. Had Bourke’s engine produced 76 horsepower at 10,000 rpm, exhaust gasses would be more like 1100 deg F, much higher than the claimed 200 deg. But as stated previously, the cool exhaust gasses were the result of poor scavenging, not from any magical combustion phenomena, and thus wrongly interpreted by Bourke.

As the engine’s delivery ratio was falling off sharply after 4000 rpm (and only 40% maximum), there is no possible way that it could ever turn up to 10,000 rpm. This effect, combined with poor charge trapping (due to the highly deficient scavenging), would never allow the high rpm, power outputs, or thermal efficiency to be obtained as Bourke stated. Air is the working fluid for any internal combustion engine – it is the properties of air expanding when heated that produces work on the pistons. If deficient air moving and trapping is occurring, as was evident in the tests, it would be impossible for the engine to ever approach the performance claims that the inventor made.

As it was the Experimental Aircraft Association whose publications brought the Bourke engine to my attention originally, I thought it honorable to write an article on my findings and publish it in their monthly magazine. A seven-page article was prepared, written in a style that was understandable by non-engineers, and that discussed the abysmal performance this engine exhibited under actual testing. A copy of this article is available at:
http://a.moirier.free.fr/Moteur/Documentation/Perf...

I received letters from readers for years afterwards, most of whom praised the fact that the engine was actually evaluated and the truth told. There were some, however, who thought I just didn’t discover the “secret” that would make the engine run as Bourke claimed. And interestingly, I met several people who actually had experience with original Bourke engines. Their comments added credence to my findings.

It is this writer’s opinion that the Bourke engine was a product of an overenthusiastic inventor who made unsubstantiated claims of high performance and fuel efficiency, mainly to draw attention to his invention in the hopes of acquiring developmental funding. Until validated test data can prove otherwise, this engine offers no revolutionary benefits and is not a valid contribution to internal combustion engine technology.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Interesting post Dave, thank you for the original background.

Not sure if you read this whole thread, but your original article is linked a few posts above your reply.

I see you may have joined our forum just to reply to this thread- did someone reach out to you or did you find this thread via a search for discussion on Bourke?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Hi jgKRI,

Thank you for the kind remarks. I joined the group because of a member informing me about the Bourke engine thread. After viewing the contents of this website, I think this will be a valuable informational source on engines and things mechanical and look forward to being a participant.

I'm a retired mechanical engineer that has worked in the internal combustion engine field for all of my 34 year career. Since retirement, I've started doing engine consulting and really enjoy being out of the Corporate America rat-race.

I'm sure there will be those that feel that my tests were poorly done, that I made "changes to Bourke's exacting specifications", used the wrong fuels, wrong carburetor, etc. I've always found it interesting that these folks have little or no experience in the internal combustion engine field and just take the claims made by Bourke to be proven facts. I've yet to see any test data from anyone that substantiates any of Bourke's claims as to performance, thermal efficiency or exhaust emissions under a loaded condition. Until I can see actual test data that that shows otherwise, I'm standing by my findings.

As the old saying goes, "Show Me The Data".

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

If your tests (and others) had been somewhere in the ballpark, maybe Bourke's ideas would have some credence. But the fact that real life vs his claims were so far apart, as well as the lack of actual data/results provided by him, show that it's just a tall tale.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Dave Kirk ... Welcome!

We've had our share of inventors show up over the years. Feel free to debunk as you see fit.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Welcome Dave Kirk!

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
The writer simply failed to achieve the Bourke Cycle! Simple as that. Plenty have failed and some have achieved it, evidently.
I know of others who have achieved powering a load with the Bourke engine, to what extent I do not know as I was not an eye witness.
I have yet to personally witness Bourke's claims regarding it's alleged power curve which is superior to any piston slapper ever made!
The man's claims about the scotch yoke being irrelivant say nothing but pure counter intention based on the need to be right about the flawed direct coupling of piston slappers. The Scotch Yoke is superior to conventional hands down! The resulting sinusoidal operation is a plus point and any engineer worth his salt will agree!
Don't get me wrong. I like piston engines of all types. The Dynacam engine and others that utilize various different forms of reverse cam arrangement prove it's viability!
Russell was into producing an engine type that required few parts and zero parasitic losses of multiple moving parts such as is the case with most piston slappers.
One thing I will note is using pump gasoline or diesel will not yield the Bourke Cycle!
Russell states this clearly in this documentary and explains why that is and anyone familiar with fuel doping agents can understand this.
As to his assertions on low EGT's being an indication of intake gasses passing dead across the cylinder directly to the exhaust port. WRONG!
Roger's prototye which I have personally witnessed ran on 50:1 premix just to be safe as it's not easy getting hold of replacement parts, yielded no smoke out of the exhaust ports. Squirting 30 weight motor oil right down the carburetor yielded no smoke out of the exhaust ports! Complete combustion? Hmmmm....scratch your chins on that!
The 001 and 015 original Bourke 30's both ran on pump gas which is not recommended but expedient, and did not use any pre-mix oiling. Proof that the crankcase oiling system works just fine as reported by Russell Bourke.
Anyway, absolute conclusive findings have not yet been achieved, no matter how much someone writes about it.
This guy could have taken video of his experiments back then. I wonder why he didn't given the time and expense of the experiments he allegidly performed, he surely could afford to buy a movie camera!
One thing still holds true today, the Bourke Cycle concerns those who stand to lose billions if it's mass produced!
And the potential for success still exists! Who's next to try?
Yeah, I could try to do it myself, and I still may! ;) I do want to know one way or the other if the Bourke Cycle is a myth or is indeed real just like Russell said it is!
And finally, WATCH! >>>>> http://bourke-engine.com/vids/Bourke30Runs.mpg
http://bourke-engine.com/vids/rlyruns.mpg
Like one piston slapper head said to Russ long ago, "we'll spend millions to prove you wrong but not one penny to prove you right!" H E L L O ! ! ! !
GodSpeed!

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Quote (Cryptoman)

I have yet to personally witness Bourke's claims regarding it's alleged power curve

Then why do you believe them

Quote (Cryptoman)

One thing I will note is using pump gasoline or diesel will not yield the Bourke Cycle!

Quote (Cryptoman)

The 001 and 015 original Bourke 30's both ran on pump gas

Which is it?

Quote (Cryptoman)

I do want to know one way or the other if the Bourke Cycle is a myth or is indeed real

Soooooo people who have done actual physical testing are idiots who don't know anything, but if you ran a test you'd be the expert who knows everything?

I politely suggest that you put your money where your mouth is and run a test (as others have done) or stop promoting an argument completely unsupported by data of any kind.

While you're thinking about that, google 'logical fallacy no true Scotsman'

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

"The writer simply failed to achieve the Bourke Cycle! Simple as that. Plenty have failed and some have achieved it, evidently."

Funny how those who achieve it don't write about and provide data showing the results (dyno testing) from a reputable 3rd party lab. I guess they are just too busy making other magical things happen?

I'm going back to my pannetone, this fruit cake leaves a bad taste in my mouth.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
"We'll spend millions to provve you wrong, but not a penny to prove you right!"
Russell Bourke
Still rings true today! ;)

You mean to tell me, after reading the Bourke Engine Documentary, UNlESS you haven't
and are relying on your piston slapper education, you actually believe it never worked as purported by Russell Bourke? What about eye witnesses? What about people that actually knew him personally and worked with him and saw these engines run?

What about the Bourke 400 truck / tug boat prototype engine?

Do you geniuses actually believe he and his investors would do all that work, spend all that money and try to make it go world wide just to create a hoax? Just to be right about bullshit? That they would all sacrafice and go through the growing pains required to push something of this magnitude forward to fruition? None of these people were rich. They were good hard working Americans earning a living and helping thier fellows while persuing their dreams doing something they had a passion for!?

LOGIC!?!? gentlemen, and ladies..

Here's an interesting thing to ponder. What would you do if you wanted to come up with something superior to a conventional naturally innefficient piston slapper that isn't trying to cock itself up or throw parts scattering?

Someone earlier stated that HCCI is impossible in so many words..WRONG!
https://arstechnica.com/cars/2017/08/mazda-says-it...

I'll be back to play somemore later!
Enjoy!

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Mazda's Skyactiv-X is not true HCCI. It's spark-ignition with essentially controlled detonation, facilitated by their direct-injection strategy, which allows them to create a stratified charge in the cylinder (roughly stoichiometric or slightly rich near the spark plug so that the spark plug can reliably ignite it, lean elsewhere but in a progressive manner so that the rate of pressure rise can be controlled and kept below destructive levels). The Bourke engine is a carbureted spark-ignition two-stroke ... evidently with enough compression to cause uncontrolled detonation. It is incapable of having stratified charge.

Once again ... Show us the P-V diagram, show us the means of ignition (and I saw those spark plugs), and how ignition is reliably achieved over the entire useful range of ambient temperature, engine temperature, and engine load.

At the moment, Dave Kirk's post indicates that the engine operates as expected ... not well.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I should add that there is no "Bourke cycle". The engine operates on the two-stroke Otto cycle, but with high parasitic loss due to the high pre-compression used in the scavenging pump (the work of which is lost during scavenging of the power cylinder), and evidently with an attempt to achieve the constant-volume combustion of the true Otto cycle as opposed to having a progressive combustion process (differing from the idealized Otto cycle) that real-world spark-ignition engines use.

The Otto cycle does not care about the means by which the volume in the cylinder is varied as it goes through that cycle.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

2
Cryptoman,

I direct this post to you as you made some observations that are totally correct.

I was not able to induce the “Bourke Cycle” in any of my testing. You suggest that the fuels I used were wrong. In the Bourke Engine Documentary, Russell Bourke mentions running engines on brown distillate. At the time, I tried to procure this chemical and could not find it. Talking to some fuel suppliers, I learned that this was a low-grade kerosene, sometimes referred to as “coal oil” (having a light brown coloration) and was no longer available. Bourke also states in the Documentary that low octane gasoline can be used. This was also tried, both in non-diluted form and with diesel fuel mixed to further lower the octane rating. I also tried Coleman lantern fuel, a non-leaded “white” gasoline, as what Roger Richard has recommended. The most intense detonation occurred using the gasoline/diesel mix – there was audible detonation occurring – not just pinging, but loud spark knock. My engine lost power and would have probably seized had I let this continue as oil temperature was approaching 300 deg F. Leaning the mixture and advancing spark timing, either separately or simultaneously, caused a further drop in power. This was not a 1-shot attempt – I spent many hours in the lab experimenting with fuel mixes and settings, with never a hint of a “Bourke Cycle”.

Regarding the scotch yoke crank mechanism, you are again totally correct – there is inherently nothing wrong with this device. It has been used on marine steam engines and more recently, a high-volume production automotive refrigeration compressor (Tecumseh Products). The Ficht company, a German corporation (and the inventors of the direct fuel injection system used by Bombardier on their DI 2-stroke outboards) have been dabbling with scotch yoke two-stroke engines for years as shown in this YouTube video:

https://www.youtube.com/watch?v=2-25aj82Nuc

The CMC group out of Australia have done some very good work in developing a 4-stroke scotch yoke engine for automotive applications. Their research work has been top-notch and is available in several technical papers from SAE. The scotch yoke does reduce the package volume of the engine somewhat when compared to the conventional connecting rod crank system. There are little or no performance gains however. Their 4-cylinder engine does incorporate a balance shaft to cancel the primary couple induced by the 180-degree crank arrangement of the opposed configuration. And, the scotch yoke/piston assembly probably costs 4X (estimated, based on experience) than that of two conventional rods and pistons to produce. So, I can understand why automakers are reluctant to adopt this technology – more expense with the only benefit being a very slight package volume reduction.

The DynaCam engine – a barrel-form axial cam engine that has been around since the late 1940’s (then known as the Hermann Cam Engine). This machine has been constructed, prototype tested, received FAA certification and has actually been flown in a Piper aircraft. The packaging is very attractive in that frontal area is small, thus ideal for aircraft applications. After all these years, it’s never made it into production. Reasons are mechanical noise – the necessary clearance between piston rollers and cam surface generates a loud “rattle” when the engine runs. Mechanical efficiency is not very high due to high piston skirt loading and resulting friction caused by the double sinusoidal cam shape employed. Finally, cam surface spalling in a relatively short running time due to the high Hertzian contact stresses induced from line contact from the piston rollers. I’m not fabricating these defects…this was told to me by an engineer that worked for the company years ago.

Bourke Cycle low EGT’s – When I did the testing and evaluation of my Vaux engine, I was working as a mechanical engineer at Outboard Marine Corp – my first engineering job after graduation. Management was kind enough to allow me a test cell equipped with a Stuska water brake dynamometer and all the test equipment I requested, as long as I did my work after hours or on weekends. I had plenty of technical volunteers that helped with the testing and data taking. I utilized the exhaust emissions equipment to analyze exhaust products and a Merium laminar element for induction airflow measurement. When running the Vaux engine at light or no load, emissions looked like any other 2-stroke engine…moderate levels of HC, low CO and NOx. When dyno load was applied and throttle opened and ignition timing and mixture optimized, the HC (hydrocarbon) emissions went totally off-scale! It is true that EGT’s were only around 200 deg F and the engine was not misfiring. The only logical conclusion is that unburned fuel mixture was escaping to exhaust due to scavenge losses. This would dilute the exhaust gas and account for the low temperatures observed.

You are correct again in stating that “absolute conclusive findings have not been achieved”. Bourke’s first engine was constructed and ran in 1932 (Silver Eagle) and we are coming up on 87 years with no real test data on any Bourke engine to verify the claimed performance. Other than the outboard motor that Bourke stated to have logged “over 2000 hours of testing”, there is no vehicle installation of a Bourke engine that I know of as being successful and actually demonstrating the engine as a useful prime mover. This raises a bit of suspicion in its validity.

Taking movies – No movies were taken of my testing. I didn’t have a movie camera at the time and movies were not typically made of engines being dyno tested. I do have some still photos of the engine and test set-up, one of which appears in my original article in Sport Aviation Magazine.

When you state “One thing still holds true today, the Bourke Cycle concerns those who stand to lose billions if it's mass produced!” sounds a bit conspiratorial. If it were legitimate, I think the Chinese would be producing Bourke engines by the millions and selling them to us in automobiles.

I watched the video of the original Bourke 30 running on the 90-degree angle drive. The engine is running no-load and I’d estimate turning about 3000 rpm. The exhaust gasses are clear with no smoke and there is no fuel spit-back from the carburetor. The sound brought back memories – sounded exactly like my Vaux engine when running unloaded. I hope the next video shows the engine actually under load, driving a dyno, generator, prop, etc. Then you’ll notice a total change in the engine’s personality – severe vibration, carburetor fuel spit-back, and dangerously high engine oil temperatures.

Please understand that I mean no disrespect to anyone, living or dead, by posting my test results and opinions on the Bourke engine. If you are a friend of Roger Richard, please encourage him to run performance tests and post them on the Bourke Engine Website. I respect Roger in his dedicated and untiring faith in the Bourke engine. The fact that he’s constructed an engine from scratch plus purchased original Bourke 30’s shows his commitment and I admire that. I visit his site occasionally and never find any test results - only remarks that the engine is running a generator and producing around 30 horsepower. This is not conclusive test data – a real dyno-generated power (or torque) vs rpm and fuel consumed vs power information is the minimal, final proof that the engine is legitimate.

When I began my test and evaluation of the Bourke engine, I was very much convinced that there was something to be uncovered in this machine. I was a total proponent of the combustion phenomena that yielded hitherto unharnessed energy that could be controlled by a two-stroke engine cycle using a scotch yoke crank mechanism. In other words, I read the Bourke Engine Documentary and bought the pitch. I tested my engine to the best of my ability, working with others in the engine field, and working in a fully-equipped engine test lab. I reworked my Vaux replica to be exactly like the original Bourke 30 from Bourke-drawn blueprints. Most all of the costs for this entire project were on me – and it wasn’t cheap! I gave it a fair and unbiased evaluation and bottom line – it performed nothing like what Bourke had claimed.

I’ve always considered myself as an “engine guy”. It is my lifelong fascination with engines that compelled me to get my ME degree and spend my whole working career in the engine business. So, I guess I qualify as a “piston slapper” to which I am honored. I’ve also worked on turbo machinery and rotary engines, so “turbo-turd” and “Wankel whacko” apply as well.

Cryptoman – Please let us know your educational background and your experience with engines. It just helps us all better understand your passion for the Bourke engine.

Respectfully,

Dave

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
Ahl, beh bach! ;)

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Glad to have a fellow engine guy join, and wow a huge asset to this site. Welcome Dave Kirk.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Mr. Kirk not only spent his own money to acquire the best replica of an original Bourke engine for testing, he subsequently built a four cylinder radial engine of his own design which incorporated a scotch yoke. He exhibited and ran his X-4, air-cooled engine at the EAA convention many years back. The engine produced respectable, (approximately 1 hp/cubic inch), power. As one of the few people who have designed and built a scotch yoke based I. C. engine, he has made considerable effort to explore the virtues of the mechanism. His comments on the scotch yoke are much more than speculation.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Unfortunately, the details of the air pump mechanism don't affect the Carnot efficiency limitations.

Steve

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

My German is not good, but I couldn't help but notice that the name Ficht appears in the youtube link that Cryptoman posted.

Ficht, if it is the same company (probably), developed a direct-fuel-injection system for two-stroke spark ignition engines, which was subsequently used by Outboard Marine (Evinrude) for some time. I believe this system has since been replaced by other technology, but it was around for a while. Obviously the intent with all such direct-injection systems on two-stroke engines is to address the fuel consumption and emission control shortcomings of traditional carbureted designs.

The OMC engines obviously used a traditional crankcase-scavenged bottom end, although with oil injected directly (as opposed to being premixed with fuel - necessary, since the fuel no longer passes through the crankcase).

https://www.youtube.com/watch?v=-QN-5uTZC7w

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
Good morning friends!
Thank you for the validations Dave!
https://youtu.be/2-25aj82Nuc
https://youtu.be/2-25aj82Nuc?t=101
Scotch yoke engines don't work eh?
By the way, the Bourke engine was a MONO STROKE engine, not a 2 STROKE by way of the 1 piece connecting rod mechanism. PROOF of the 1 stroke cycle!
A Vaux 500 is not a Bourke Engine. It's a modified version of the original Bourke 30 where Melvin too lots of short cuts.
Also, Melvin Vaux came up with what he thought was an improved version of the original Bourke 30.
It utilized a square cup with a radius cut out of each rod shoe to increase dwell time at btc and tdc.. it also used a center drive gear as it's pto where a total of 4 cylinders were driving at HIGH RPM!
The engine ran on natural gas and other fuels and drove a genearator under load for quite a while.
Further, Melvin created a 350 cu 2 cylinder version (known as the Vaux 200) and ran an irrigation pump with it on natural gas for years. It has been on display in a museum in Shafter Ca for years now since Melvin's passing.
I personally witnessed the DeVaux 4 cylinder engine run and when it did, it made a horrible rattling noise which was clearly the outer surface of the 3 layer bearing rapping against the shoe face every time the opposing cylinder fired! = JUNK in my opinion.
The Vaux 200 did not rap because the shoe facings were flat.
Just because someone tried and failed to achieve the Bourke Cycle doesn't mean it's not achievable, it simply means the experimenter failed to prove conclusively one way or the other that the Bourke Cycle is a myth!
If one simply looks, reads, studies and duplicates Russel's work, one should be able to achieve the same results as Russell! There are video's of live Bourke engine runs that prove this FACT!
There are no video's or any real evidence of the experimenter's findings one way or the other and one cannot write TRUTH into existance, no matter how many pages! PERIOD!
Another thing the experimenter proves is that "one must throw away all they've learned about conventional engines and start completely over to understand the Bourke Cycle!"
This fact still frustrates and confuses conventional engineers to this day!
Fitch was obviously on the right track in proving Russel Bourke right! And so they did! Well done Fitch!
Article from HotRod Magazine 1954! Russell was making waves and history!
http://www.projectbourke.com/hotrod.htm
Enjoy!
Cryptoman

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

What is the P-V diagram of the "Bourke cycle"?

The page that you linked to indicated "At about 90 degrees before top dead center, ignition occurs as compression continues." I cut-and-pasted those from the linked article.

Really?

"Since all heat is extracted at the top of piston travel" ... Really? And ignition happened 90 degrees before top dead center? What happened to the combustion that occurred after ignition and before top dead center? What part of the cycle was it in when *that* happened?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Quote (Cryptoman)

By the way, the Bourke engine was a MONO STROKE engine, not a 2 STROKE by way of the 1 piece connecting rod mechanism. PROOF of the 1 stroke cycle!

I know I'm wasting my time here. But... no.

A '1-stroke engine' would be an engine where the piston moved from TDC to BDC and never returned.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

By the same argument, the relatively conventional Fiat 1.4 in my daily driver is a one-stroke engine.

By the same argument, the relatively conventional Mopar 3.6 in my van is a two-thirds stroke engine.

smile

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

According to the old Hot Rod article it seems likely it was not Mr Bourke who called it a "one stroke." As I read thru what Cryptoman has provided, David Wolfe, Founder, Bourke-Engine.Com, is the originator of the "one stroke" .

Unfortunate.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I don't understand you Cryptoman. You have several anecdotes about various engines reportedly using "the Bourke Cycle" which you cite as evidence that it's feasible/reliable/superior. Yet you've said a few times that even you, an energetic supporter, are not sure if this cycle is real.

Dave Kirk acquired a replica engine and did actual testing. His article notes some of the design changes you mentioned and he has actual data, something that is conveniently missing from other claims of "replicating" the engine. You ask why he didn't record it on camera (an expensive proposition in 1980) to imply his tests weren't accurate, which is rich considering none of the supporters have as much documentation.

Bourke was just another snake oil salesman trying to earn money by making outlandish claims and the mythology and lack of testing to support his claims show that.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I have a cure for cancer. I have no evidence supporting my claim, but many sites on the internet support my ideas. While those sites will help those with an open mind grasp my approach, be forewarned one must throw away all they've learned about medicine and start completely over to understand it. Pay no heed to the many critiques of my solution by so called "medical experts;" one cannot write TRUTH into existence, no matter how many pages! (Please ignore those who say I'm the one trying to write truth into existence).

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Videos of running engines, but no videos of engines running with torque/power measurements, nor of fuel consumption. Pretty basic stuff, but no video, much less any other documentation.

Love the German videos. 5 minutes of black screen...? And again, no power measurements, no fuel consumption data, no data or documentation to speak of.

This pannetone is delicious.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

One stroke? Wankel? No stroke?
Just asking. I got lost trying to visualize a working one stroke.
Diesel hammer used for pile driving?
Diesel Hammer. One stroke?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

RodRico (Automotive)14 Jan 19 14:02
I have a cure for cancer. I have no evidence supporting my claim, but many sites on the internet support my ideas. While those sites will help those with an open mind grasp my approach, be forewarned one must throw away all they've learned about medicine and start completely over to understand it. Pay no heed to the many critiques of my solution by so called "medical experts;" one cannot write TRUTH into existence, no matter how many pages! (Please ignore those who say I'm the one trying to write truth into existence).

Hi Rod. Please link me to some of your web sites. I want to become a believer! I know that big pharma is suppressing your idea because it will ruin their business model. (They are too stupid to realise that if one of them breaks rank and markets your cure, they will dominate their opposition overnight)

Same goes for the Bourke engine of course. World beating technology suppressed by companies too stupid to realise they could make a fortune by getting in first and marketing it.

je suis charlie

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Quote (waross)

One stroke? Wankel? No stroke?
Just asking. I got lost trying to visualize a working one stroke.
Diesel hammer used for pile driving?
Diesel Hammer. One stroke?

Still a 2-stroke, a free piston 2 stroke engine. It's the same cycle as an opposed piston engine except the bottom piston doesn't move much.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Reminds me of That 70s Show:

Quote (Hyde)

And they've got an air cooled fiberglass engine, man. It runs on WATER man.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

4
Gentlemen –

Thank you to all that have welcomed me to this site…much appreciated.

I was disappointed in the outcome of the Bourke engine evaluation, especially after all the time, money and dedication that I expended. There was good that came of this though. The Sport Aviation article put me in touch with a number of people that had experience with Russell Bourke personally, some of whom constructed and tested their own Bourke engines, and one person who actually dyno tested an original Bourke “30”. I found it interesting that his test results were almost identical to mine – that is, 9 bhp @ 4000 rpm. In conversations with those that knew Bourke personally (Melvin Vaux), I learned that Bourke was hot-tempered, hard to work with, and greatly exaggerated his claims.

The feature that initially attracted me to the Bourke engine was the combining of the scotch yoke crank mechanism with the two-stroke operational cycle. In studying the patent literature, it was readily apparent that Bourke was NOT the inventor of this configuration – patents extend back to the early 1900’s describing this embodiment almost exactly. One of particular interest is U.S. Patent 981995, entitled “Motor”, January 1911. The drawings describe a 6-cylinder 2-stroke radial layout using 3 scotch yokes with crankpin yoke rollers used – uncannily resembling what Bourke patented 25 years later in 1938. One wonders if this document was originally viewed by Bourke and provided him “inspiration”?

The real attractiveness in this mechanical combination is that, due to the pure linear motion of the piston rods, the cylinder scavenge pumps (normally the crankcase of a conventional 2-stroke) can be totally isolated from the crankcase mechanism. This allows a full, circulatory lubrication system to be employed, thereby supplying undiluted oil to all of the highly loaded bearings. The pure harmonic motion of the rod-yoke reciprocating assemblies offers the potential of excellent engine balance if properly configured and counterweighted. All of these advantages are gained without complicating the basic simplicity of the 2-stroke engine. Preliminary layouts showed a very compact engine could be achieved especially with oversquare bore/stroke ratios.

Encouraged by a good friend who offered financial support, I decided to design an engine that would correct all the design faults uncovered in my prior Bourke engine testing. Due to my love of aviation and being a member of EAA, an aircraft engine application was most appealing. The ARV (Air Recreational Vehicle) market, then becoming very popular, required engines of 18 – 25 bhp and this defined the preliminary goals of the project. Initial layouts and basic calculations showed that by using 2 recip assemblies oriented at 90 degrees from each other, a compact 4-cylinder X-radial engine was possible and that 100% primary balance was achievable with proper crankshaft counterweighting. As 25 bhp was the target power at 5000 rpm (direct drive turning a 36” diameter propeller) a realistic bmep of 80 psi was selected for good reliability. These parameters sized the displacement at 25.2 cu in, or 6.3 cu in/cylinder.

Over the next 18 months, I performed all of the engineering calculations, design work, and board drawings (no CAD back then) all as a spare-time endeavor (I have a very understanding wife). All of the features found detrimental in the Bourke engine were corrected and these were as follows:
• Scavenge pump compression ratio was reduced to 1.4:1, a typical value for high performance 2-stroke engines. This was achieved by incorporation of an integral volume chamber between the cylinder and crankcase that added nothing to the weight or physical size of the engine.
• Cylinders were designed with Schnurle porting (loop scavenging) that utilized 2 main and 2 boost transfers, allowing non-deflector (slightly domed) pistons to be used. Conventional piston-controlled intake and exhaust ports were utilized.
• In the Bourke design, piston rods were supported and guided by bushings in the crankcase. The reaction forces (torque applied to engine frame) of the rod yoke assembly was absorbed by relatively small surface area bearings, contributing to high unit loads and heat transfer into the crankcase. In my redesign, pistons are rigidly attached to the piston rods with piston skirts carrying this reaction force. Only Teflon lip seals with radial compliance were used at the crankcase/scavenge pump juncture, sealing around the ground and polished piston rods.
• Knowledge of 2-stroke gas dynamics and attention to gas flow allowed non-restrictive passages and proper port time-area relationships to be incorporated. A 4-into-1 exhaust system was designed to utilize inter-cylinder tuning, allowing properly timed positive pressure wave to arrive prior to exhaust closure, contributing to good trapping efficiency.
• A gerotor oil pump supplied oil from an oil tank for direct spray lubrication of the rod yoke bearings. I did use the yoke roller design as lubrication requirements are greatly simplified versus a pressure lubricated slider block. Oil return back to the tank was via gravity. Cylinder lubrication was via cylinder located, drilled oil ports communicating with oil mist in the crankcase, with one-way check valves being used. Vacuum created in the scavenge pump drew oil mist onto the bore surface.

Patterns were made, castings completed, and machining for the first prototype were done by local machine shops and friends. With very little development work (mostly sorting out the lubrication system), the engine made it’s target performance goals. After a little tweaking, best power recorded was 27.5 bhp @ 5300 rpm. For power measurement, I constructed a torque stand whereby the engine was rotationally supported and balanced. Torque measurement was read from a 1-foot moment arm directly to a spring scale. I had a selection of 3 different-pitched propellers such that I could run 3 load points – sufficient for initial evaluation.

I displayed and ran the engine for 2 consecutive EAA Fly-In events in Oshkosh WI. It received lots of interest, however it was never produced due to the legal liability aspects involved with such a product. I put about 30 hours of WOT testing on the first prototype with no failures or surprises. It was very smooth in operation, with only very slight vibration induced by the force couple due to the axial offset of the reciprocating assemblies. Best bsfc recorded was .606 lbm/bhp-hr at 4800 rpm (cruise setting) and .673 lbm/bhp-hr at 5000 rpm WOT. While these figures are by no means exemplary, they are typical of carbureted 2-stroke engines employing exhaust tuning. Final specifications were as follows:

Bore – 2.313”
Stroke – 1.500”
Total Displacement – 25.2 cu in
Compression Ratio – 7.0:1
Overall Diameter – 16.25”
Length – 21” (with Vertex Magneto)
Weight, Complete – 60 lbm
Fuel – Auto or Avgas, 100 octane low-lead avgas preferred
Best Ignition Timing – 28 deg btdc
Bmep – 78.6 psi
Rated Power – 25.0 bhp @ 5000 rpm

I wrote and presented a technical paper on this engine at the 1985 SAE convention in Milwaukee WI. For those interested, it is still available from SAE:

https://www.sae.org/publications/technical-papers/...

The paper describes the design rationale and specific engineering details that are too lengthy to discuss here.
I must advise those that are proponents of the Bourke engine – my X-4 IS NOT A BOURKE ENGINE! It exhibits no magical combustion phenomena, no incredible fuel efficiency, no cool exhaust temperature, no reverse-toggle action, no cyclonic turbulation, etc. It is a 2-stroke, homogeneous-charged/scavenged engine that performs comparably to a conventional exhaust-tuned engine. Benefits gained by the configuration are in operational smoothness, small package size, and employment of a more-conventional 4-stroke lubrication system…that’s it!

The take-aways from this project were the personal satisfaction in designing my own engine that met all the performance targets without anyone micro-managing or “supervising”, no legal department to contend with, no sales-marketing-purchasing department, etc., that we as engineers face in the corporate environment. Most of all, it demonstrates that a scotch yoke 2-stroke engine is a perfectly workable concept. Scaled up and equipped with a direct-cylinder fuel injection system, it could be a very attractive aircraft powerplant for general aviation.

Pictures of the “short nose” version of my X-4 appear below. Engine shown with the Vertex mag and exhaust system removed.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

The scotch yoke is not the only method of obtaining linear con rod movement.
The Wärtsilä-Sulzer RTA96-C uses a cross head with a slider and a second con rod to the crank shaft.
They may be using the space below the piston to charge an adjacent cylinder rather than the same cylinder.
I can't find the details but this arrangement could possible be more efficient that feeding the same cylinder.
With suitable timing, the air may be transferred to the second cylinder with little increase in pressure, saving the heat losses associated with compressing the scavenge air.
Here's the link. For some reason that I can't put my finger on, I will wait for a second source of information before accepting all the details completely.
Wärtsilä-Sulzer RTA96-C

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

DK - your 4-cylinder engine is a very neat and compact design - surely it would have commercial applications and value?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Kirk,

Very interesting. I'd like to see your engine posted as a separate thread rather than under this silly Bourke thread.

I've designed a new engine that also targets light aviation. Mine is a cam driven opposed-piston two-stroke HCCI six cylinder radial (rotating cylinder) with an integral piston driven air pump for every pair of opposed pistons. In this engine, piston side loads resulting from interaction with the cams is absorbed by sliding bearings in the rotor, so it will have some the same issues as a Scotch Yoke design. It's a high risk endeavor in my opinion, but still worthy of pursuing. I'm just now beginning fabrication of the prototype which, if successful, will hopefully draw interest from an established manufacturer. Per my analysis, the 12.38cc (2.06cc per cylinder) prototype in which each cylinder completes four full cycles per revolution should produce BMEP of 8.24 bar, 2.4 HP, and 4.8 lb-ft torque at 2626 RPM with 52.8% brake efficiency (63.2% thermal) and BSFC of 0.262 lb/hr/hp in 120.8 cubic inch volume. I'd be interested in hearing your observations some day if you're interested.

Great work on that engine you show! It really deserves it's own thread.

Rod

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Rod, without going back to check, your specifications seem to have moderated somewhat. They are now all sitting in a realistic zone - except - thermal efficiency. If 52.8% BTE was possible in such a small engine (52.8 is the same BTE as the biggest, most efficient recip' engines in existence), your target market would be every internal combustion engine application on the planet.

je suis charlie

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

gruntguru,

My numbers constantly evolve as I tweak the detailed build parameters (for things like minimum wall thickness), but I don't recall any big changes recently... biggest was a drop in peak combustion temp from 2150K to 2100K to reduce NOx formation. I know models are only approximations, so my predictions are just approximations. They do suggest, however, that there's a reasonable chance this engine will be worth the effort. Unfortunately, I won't have real numbers for quite some time (I only last week started ordering fabrication equipment and still haven't finished fuel injector design). I don't find the mathematical predictions too surprising, however, because the engine processes as much air mass per revolution as a 49.5cc two-stroke (because each cylinder completes four full cycles per revolution) yet produces only 14% more HP and torque than a Honda GXH50 four stroke geared down to the same RPM. The big gain should be in fuel consumption and volume where the math indicates 45% and 73% improvement of the GXH50... if I come anywhere close to those figures, I'll call it a success.

Rod

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
Tmoose (Mechanical)14 Jan 19 13:17
According to the old Hot Rod article it seems likely it was not Mr Bourke who called it a "one stroke." As I read thru what Cryptoman has provided, David Wolfe, Founder, Bourke-Engine.Com, is the originator of the "one stroke" .

Unfortunate.

WRONG! Dude, read the Documentary! ;)

Dave Kirk!
Thank you, brother! Excellent work! I had no idea this had finally been done empirically!
Has anyone heard of John Allens' scotch yoke engine called the VLB for Very Lean Burn?
It was a single overhead exhaust valved / ported induction with variable under piston transfer pumping....supposedly was successful but due to harrassment and attempted circumvention of his authority and ownership of his patents, he evidently destoryed the entire project and dumped it in the river thames!
I like the design. I think it was much more viable than the original Bourke engine design.
I know of Melvin Vaux's diatribe on Russell but he too was a hot head know it all and continued with Russell's design making small modifications such as a modified cast crank out of a compressor and z cut slots in the piston skirt for relief and smoothing out sharp transfer pumping losses.
I personally interviewed Melvin. Smart guy but was mentored by Russell, evidently.
Melvin ran a 200 cu in 2 cyl. version of the Bourke engine utilizing a square cup in place of the 2 piece yoke plate setup and a half shaft where the cup had a backing plate to prevent warpage under pressure by both cylinders. It was supposedly started on 1K then transitioned over to natural gas and ran a field irrigation pump unattended for thousands upon thousands of hours where he lived in Nevada until he passed on.
Russell also stated that "engines will forever be improved upon" when he admitted his design was not the last word as such!
Snake oil salesman, someome said? What are YOU trying to sell buddy?
You need to read the documentary or stfu!
Again, love your work and report Dave Kirk! Well done!
I have access to Russell's experimental 400 4 cylinder truck / tow boat engine by the way.
Cryptoman



RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I'm not selling anything while you continually advocate support for a design that has no justifiable explanation (a mysterious new cycle counter to known physics, and no actual explanation by the supposed inventor) and no actual data showing it works as advertised (see Dave Kirk's personal tests and the lack of data by every other proponent). Videos of engines running without data are not acceptable.

No one is saying engines aren't continuously being improved as that's clearly not true. There are actual, real, quantifiable improvements being made. But this entire thread, and your comments, imply that "the man" is hiding some super efficient engine in a barn in an effort to...not make money by selling the most efficient car?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Two-stroke uniflow-scavenged engines with ported intake and valved exhaust are known in history ... notably, Detroit Diesel two-strokes were like that.

The combustion concept is independent of whether the mechanism underneath uses a Scotch yoke or conventional connecting rods. Quite a number of more modern two-stroke engines have been developed, and some have been in production or are in production. If we confine the discussion to spark-ignition, several notable examples include the Orbital air-assisted direct-injection concept (in production by Aprilia/Piaggio and Mercury Marine), and the above-mentioned Ficht direct-injection system (in production by Evinrude, which was bought by Bombardier, and its successor is used to this day in snowmobiles and outboard motors using the E-Tec name). Bombardier had another concept called SDI (Semi Direct Injection) which involved using a more-or-less conventional automotive fuel injector located in the transfer port so that injection could be timed late enough to minimise fuel crossover.

These concepts generally use some form of stratified charge in order to facilitate ignition at partial engine load. They generally have large efficiency gains beyond carbureted (or premixed-charge) two-strokes due to less fuel short-circuiting out the exhaust port and more reliable ignition. They are not, however, magic bullets. None of these have found automotive application ... even with catalytic converters, they are still not capable of compliance with automotive emission standards.

These engines don't use uniflow scavenging ... but uniflow scavenging isn't a magic bullet, either.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Gentlemen –

I thank you all who responded favorably to my X-4 engine endeavor. Your comments are greatly appreciated! It may have commercial value as an RPV (remote piloted vehicle) engine but I would not want to pursue any man-carrying aircraft due to the liability situation.

Rod – your engine sounds interesting. I’m sure we would all like more details but understand that you may not be in a position to share at this time. Remember, Carnot-cycle efficiency determines the maximum thermal efficiency and for most all IC engines, 65% is maximum. Best mechanical efficiency is around 85% so these are realistic limits. Best of luck and please share what you feel that you can.

Cryptoman – by all means, get the Bourke 400 restored to operational condition and attempt to run it. Should be an excellent demonstration as to why the engine project mysteriously vanished back in the heyday. My prediction is that vibration will be extreme due to the 180 degree crank arrangement and simultaneously firing cylinders will make coupling to a dyno a real challenge. Just be sure to post your findings, no matter how disappointing they may be.

Brian P – thanks for your excellent post on DFI 2-strokes. I worked at Mercury Marine during the ‘90’s and our group was responsible for adapting the Orbital DFI system to the 3-liter V-6. Turned out to be an excellent product. The Orbital is considered a dual-fluid system; compressed air delivers fuel into the combustion chamber in close vicinity to the spark plug, enabling fully stratified operation right down to 650 rpm idle, with no misfires. At WOT, fuel trapping efficiency was around 96% which enabled the engine to easily match 4-stroke engines in bsfc. The engine could be calibrated such that a catalyst could be fitted but max power took a hit. Since there were no regulations at the time requiring a cat, we went for the max performance calibration. Air/fuel mixing was so complete that A/F ratios of 15:1 (stoichiometric) could be run at WOT and thus engine would match a carbureted engine at full power.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
http://www.bourke-engine.com/engine/vlb/
I cteated the animation on a 2D cad program called Disney Animation Studio and filled in the colored gaseous movements frame by frame in Paint! ;) It was created based on John Allen's critiques over the net...
Invented by John Allen in the 1980's..

Ficht Bourke Engine...
It is an exact replication of Russell's engine and it's running with very little vibration per Ficht's claims. One can tell it's producing torque as it's driving a full size prop' / air pump via direct drive. Just like Russell's radials did back in the day.
https://www.youtube.com/watch?v=2139YQElqIA

Dave, your tests although well done, were flawed by using 100 octane fuel. Russell specifically stated NOT to use such fuels to achieve the Bourke Cycle! Not attacking your excellent work, just stating facts.
There is evidently a fuel mixture Russell used to achieve the stated results!

The Bourke 400 has been completely restored to original condition and due to the engineers that got hold of it after it was wrested away from Russell, the cylinder heads are being redone to original specs'.
Testing should occur sometime in the forseeablek future. One of the orignial 400
investors and witness who should still be alive, stated it was running great for many hours. It was indeed running the Bourke Cycle! 200HP at 2K rpm's as stated in the Documentary.

Melvin Vaux had a 4 cylinder 500cc boxer driving a genset under load in video which I do not have on hand. One also shows him running his 2 cylinder 200 irrigation pump.
I still refuse to believe that Russell was some sort of snale oil salesman/huckster. There's just no way he and many others would put so much time and money into the projects if it was bullshit! NO WAY!
http://www.rexresearch.com/vaux/vaux.htm
The vaux engine animations were done by me also.
I witnessed a test run in PA years ago. It was a noisy clattering thing due to the radiuses that followed the arc of crank rotation cut into the shoes which caused a definate bearing slap at the beginning of each power stroke! The alteration to the shoes was an attempt to optimize dwell time to achieve a more complete combustion cycle.
Melvin's original boxer version had flat shoe faces and evidently ran fine on multiple fuels.

GodSpeed!







RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Hi Cryptoman,

On Jan 17 you said -
Tmoose (Mechanical)14 Jan 19 13:17
[indent][According to the old Hot Rod article it seems likely it was not Mr Bourke who called it a "one stroke." As I read thru what Cryptoman has provided, David Wolfe, Founder, Bourke-Engine.Com, is the originator of the "one stroke" .

[indent]
Unfortunate.

WRONG! Dude, read the Documentary! ;)

=================================
I based my speculation on the link you posted back on Jan 13. Since the author of the Hot Rod article called it a two stroke, apparently after interviewing Mr Bourke himself.
http://www.projectbourke.com/hotrod.htm

The "Original author of this (Hot Rod) article, George Hill, calls the Bourke engine a 2-stroke. It is not a 2-stroke engine.
[indent]It is a 1 stroke engine taking care of all 4 cycles in one stroke 2 times per revolution!
[indent]
Edited and reformatted for clarity and content by David Wolfe, Founder, Bourke-Engine.Com."

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Same word, different definitions.
Different strokes for different folks!

Quote (George Hill?)

It is a 1 stroke engine taking care of all 4 cycles in one stroke 2 times per revolution!
Are we down to one half stroke now?
I can see a double acting steam engine being classified as a one stroke.
Each stroke in either direction produces power.
Now how can we implement that in an internal combustion engine?
Seriously the main point is that there is a chamber above and below the piston and isolated from the crank case. That is also done in the big Wärtsilä-Sulzer RTA96-C
The second chamber requires a rigid con rod and seal.
The Wärtsilä-Sulzer RTA96-C uses a cross head and a second con rod to transform this linear motion into rotary motion.
The Burke uses a Scotch yoke.
I imagine that this could also be done with a cam arrangement.
I am wondering about the efficiency of compressing the pre-charge and losing heat to the cylinder walls or crank case housing and then losing a little pressure and volume as the pre-charge cools as it expands. Lost heat that must be made up in the compression and power strokes.
How does that compare to the efficiency of a low pressure scavenging blower as used on the old Detroit 2 cycle lines?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

here is another ultra short stroke twostroke con engine.
Link

Link

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare
www.sixstroke.com

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

This talk of "one stroke" engines is nonsense. Even a double acting steam engine is a "two stroke". The space above the piston (a "working volume") is driven down by steam on the power stroke and exhausts the steam during the upstroke where the cycle recommences. The space below the piston is a second "working volume" executing a separate thermodynamic cycle. Likewise a scotch yoke engine with two pistons combined to form a single rigid body, has two working volumes and is effectively a two cylinder engine.

je suis charlie

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Wasn't the only nonsense spouted by that engine's inventor or its proponents.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

malbeare,

It was only after clicking your link that I realized you meant to say "here is another ultra short stroke twostroke cam engine." Reading the two articles you linked, I must say I found a good number of surprising technical statements and claims. Far too many to go into, frankly.

The comments about the Split Cycle LLC engine made by the firm's president in 1998 at this page are damning and lead me to think the project was doomed to failure (though only after several changes in ownership... Split Cycle LLC -> QVEN Limited -> Industria Limited -> ??).

The tale of woe surrounding this particular split cycle engine is reminiscent of the Scuderi Split Cycle Engine that was the subject of an SEC investigation and lawsuits against the company by Hino Motors, a subsidiary of Toyota, back in 2015 resulting in seizure of Scuderi's bank accounts. The Scuderi Group (www.scuderigroup.com) lists all the associated patents but doesn't appear to offer a product.

The only split cycle I know of that's still being pursued is the Tour Engine (www.tourengine.com) which is currently working a couple of DARPA and Department of Energy contracts.

Rod

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Examples of 1- stroke engines - pistol, rifle, shotgun, cannon.

The engine business has a rich history of inventors taking money from uninformed investors. Remember the Fish and Pogue 200 mpg carburetors? More recently, the Rand-Cam engine? How about the "Mighty yet Tiny" engine?

https://www.youtube.com/watch?v=wPc06A8FwN8&t=...

Talk about a snake oil salesman! Most of these guys have convincing stories of how their engine is smaller, lighter, more fuel-efficient, etc., without ever constructing a running prototype. They may have a model that runs on compressed air but this is a long step away from a running engine. And of course, test data is never to be had.

I believe that most of these inventors start out with an idea (the easiest part) which they legitimately believe in, but have absolutely no training or education in the field. They quickly get in over their heads after extracting money from the gullible, then quietly disappear into obscurity.


RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Another common theme is that the inventor somehow gets the idea that a conventional crankshaft and con-rod arrangement is "inefficient", that moving the piston one direction and then the other somehow has a lot of lost energy, etc. Or that there is a lot of friction in the piston rings ... which has an element of truth, and yet the means by which their own inventions are sealed has not only a comparable situation but is usually a nightmare to seal and lubricate properly.

The "split cycle" engines all brag about overexpansion - more fully expanding the power stroke. This is another thing with an element of truth to it. They never talk about the heat and pressure losses associated with their crossover valve, which also has to live in hellish conditions of heat and lack of lubrication. But there's another way to achieve overexpansion ... Fiddle with the valve event timing on an otherwise-conventional engine. It's called the Atkinson cycle. Lots and lots of current production engines use valve timing trickery to achieve this, particularly at part load. There's two such engines in my driveway right now. Sure, it's less glamorous.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Dave Kirk,

I agree 100%. The primary value of math models, in my opinion, is to educate the designer regarding the interactions between a very large number of variables contributing to engine performance. The absolute accuracy of the models isn't very good until a couple of loops of model, build, test, refine, and repeat cycles are complete. Even on the first iteration, however, they provide valuable information that can prevent an engine designer from getting seduced by one aspect of the design without considering the impact on the other design elements. I can't count the number of times I was *sure* I was onto a great improvement when considering only one aspect of the design only to discover it didn't work well with other design elements in the models!

Sadly, there are many "engine designers" lacking sufficient knowledge and experience to even know what they *should* know but don't (ignorant of their own ignorance). The result has been a very long string of failures and widespread skepticism by potential investors. This history is what led to my decision not to even *bother* seeking investment until after I had build a prototype and seen encouraging results in testing by a 3rd party. One reason I decided to build the smaller prototype was because it allows me to build a second and possibly third test platform (motoring dyno, sensors, controls, etc.), each complete with an engine, that could be affordably constructed and shipped to testers.

Brian,

The magic being worked using computer controlled valves, spark, and fuel injectors is astonishing, isn't it? Heck, I think even Mazda's Spark Assisted HCCI engine is pretty much a common engine with clever control over its key elements.

Rod

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
Hey Guys!
So, the infamous 1 stroke, myth?
Look, it's quite simple.
The scotch yoke plates, conn rods, pistons arrangement of parts all connected together = 1 piece!
2 two stroke cylinders on either end.

Come on now....think!
During 1 stroke i.e. 180* of crank rotation we get -
Left end = up stroke = right end = down stroke...
Left end cycles = compression and intake = 2 cycles
Right end cycles = power and exhaust and transfer = 3 cycles
All five cycles simultaniously occuring during 1 stroke = Mono Stroke...

No such thing as Mono cycle, unless you're riding one! ;)

Loved the 6 stroke engine! What a torque monster!
Love all the other cool renditions out there too! Especially the ones that actually work!
Russell's goal, which he achived in his design, was zero parasitic moving parts!
I'm sure any of you will agree, the less parasitic losses, the better!
We're all interested in maximum efficiency i.e. adiabatic operation which is the ultimate goal in any thermal energy converter!
Near to full adiabatic operation was evidently achieved by the Bourke Cycle.
That's the rumor and I'm sticking to it! ;)

Peace!



RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

2
No, it is not a one-stroke engine. It is a two-cylinder two-stroke engine in which you are stuck with an opposed layout. By your same reasoning, the conventional inline-four 4-stroke engine in my car is a one-stroke engine. (All four events - intake, compression, power, and exhaust - are simultaneously happening distributed amongst the four cylinders.) Accept it ... the Bourke design is a two-cyilnder two-stroke engine. It has two chambers in which the operating cycle occurs separated by 180 degrees of crank rotation.

While your concept statement of "the less parasitic losses, the better" may be true, the problem is that (as RodRico alludes to) just focusing on the number of moving parts ignores a whole series of consequences. For example, the Bourke layout over-compresses the precompression chamber and then throws that work of compression away during the subsequent scavenging of the power chamber, thus encountering a parasitic loss associated with the gas transfer. (Dave Kirk alludes to this as well, and rectified that by simply allowing additional volume for the scavenging-pump cylinder. But doing so deviates from Bourke's dimensions ...)

Adiabatic operation may indeed be an "ideal" in some ways but that also has a series of consequences. Some decades ago, there was an attempt to construct an engine out of ceramic components that could operate at high temperature so as to eliminate the cooling system "losses". Problem is ... you still can't stop the heat transfer between gases and surfaces. High-temperature surfaces pump heat INTO the working fluid in the intake and first good part of the compression stroke. Aside from reducing volumetric efficiency, it increases the temperature at the end of the compression stroke. That is not a big problem for a diesel engine since there is no fuel in the intake charge (aside from raising NOx emissions!), but it is a big problem for a normal premixed-charge spark-ignition engine, probably forcing the compression ratio to be lowered.

I see nothing about the Bourke engine that would cause heat transfer between gases and surfaces to magically be stopped. (And if there is such a thing, it could equally be applied to an engine with conventional layout. It's independent of the use of a Scotch yoke. It's independent of the use of two linked opposing cylinders.)

For what it's worth, if adiabatic operation of a diesel engine were really a desirable thing, you would think that ceramic piston-tops would show up in production engines, since there is no issue with detonation or preignition. And yet ... the automotive diesel engines that I am aware of, all use aluminum pistons ... not even steel or cast-iron, which have lower heat transfer coefficients and can operate at higher service temperatures.

Maybe there's a reason for that. Hmmm, what could it be??

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

cryptoman,

We get it. Nobody is confused. We're just objecting to your distorting the commonly accepted use of the term "stroke" in reference to engines.

Neither I nor, I suspect, anyone else will agree "the less parasitic losses the better" without comprehensive analysis showing the *cost* of eliminating those losses in other aspects of the design. That's what both Kirk and I were alluding to when mentioning folks who get fascinated by one aspect of a design without comprehending the whole system and all its variables.

Yes, renditions are cool. They're even cooler when they explain the operation of a working engine. The ultimate, however, remains engines that have been tested by third parties using established methods. That's how engineers separate ideas that actually work from appealing *looking* ideas with no substantiation other than flowery words and high expectations from non-engineers lacking any knowledge of thermodynamics, friction, air flow, and so forth.

Rod

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

(OP)
Acadamia! The art of being right! :D

https://youtu.be/J2weoTGsi5c?t=204

Russell also brought up, if not created the idea of the Free Piston engine!

Russell put his money where his mouth was and was evidently successful in proving his theories in many ways!

The game goes on!

Peace

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Greg.
I resigned when I realised that I was just the carrot in the investor rippoff

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare
www.sixstroke.com

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Liquid piston engine?
Like a Nash vacuum pump running as a pressure pump into a continuous combustion chamber.
The exhaust exits through a larger displacement Nash vacuum pump repurposed as a motor and running on a common shaft.
This may be best for marine applications so as to have a ready supply of make-up water.
I can see the heading now:
The Liquid Piston Engine Solved Virtually All Imbalance Problems With Only 1 Moving Parts!
There's something about this thread that keeps sending my mind off into the weeds.
Still, I can't give it up. Grin

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

gmaslin,

Thanks for the vote of support. My predictions and expectations vary as I nudge the design to reflect what I learn from others kind enough to offer feedback and as I refine the final prototype design. Factors impacting the prototype have been overall size (driven by the tools I plan to use to make it) minimum wall thickness (which I set to values from machine shop guidelines), and decisions regarding key design features (seals, lubrication, cooling, etc.). I recently, for example, decided to eliminate the integrated centrifugal fan because I'm targeting aviation and it's very simply for me to use prop wash over finned oil coolers to do what I was doing with a much more complex (and uncertain) centrifugal fan.

I don't see myself *ever* advocating my engine for automobiles. My primary target market remains light aviation because I think it will ultimately be the only place we continue using internal combustion rather than electric propulsion (batteries are quite heavy and limited in capacity). Remember, it's going to take years for me to get my motor running and optimized. In that time, I believe internal combustion will still be used in automobiles, but primarily in a hybrid configuration in which the engine is used as a generator only. Auto makers also invest a fortune in their designs, service large markets, have great minds, and deep pockets while makers of small airplane/drone engines continue using dated designs due to their comparatively small R&D budget. The small aviation engine is a good place to operate in my opinion.

Rod

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

4
For every "new engine concept" that is legit, well researched and technically sound, there are a thousand that are not. Of those 1,000 at least a handful get to some stage of "commercialisation" that can only be described as "ripping investors off".

As far as the Bourke engine goes. I don't know enough about the history to declare Bourke a snake oil salesman (sometimes the inventor is simply an innocently naive believer in his own concept) but it will be obvious to any engineer with a background in ICE's that there is no magic in the Bourke Engine.,

je suis charlie

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

On the topic of other similar engines, technically sound or otherwise, it may be worth taking a look at Honda's attempt at a well balanced flat twin as seen here: http://www.freepatentsonline.com/7434562.html

I have great difficulty in comprehending just what is going on and how, but it is a fascinating and complex mechanism anyway.

PJGD

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Thanks for that link PJGD. The mechanism is the same as the Neander, with a few enhancements.
1. Splitting one connecting rod in two so the two pieces can "straddle" the rod on the other crankshaft. This allows the crankshafts to be moved closer together.
2. Duplicating the three rods and one piston on the other side of the cranks so each crank carries 3 rods.

je suis charlie

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

gg; Thanks for that quick summary of the Honda arrangement; I did not have the time to look at it closely and I struggled to make sense of it. I am of course familiar with the Neander arrangement and the Paul engine etc. all based on the Lanchester layout.

PJGD

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I hate to see this thread die, so here’s a small contribution to keep it going.

After writing that article for Sport Aviation magazine on testing the Bourke engine, I received many complimentary letters (pre-internet days) on how much readers appreciated an honest evaluation of this controversial engine. A few were not very kind, essentially stating that Russell Bourke was way ahead of me in the understanding of engines and that my testing was flawed in virtually all respects. To these people that blindly believed that everything that Bourke stated was fact, I labeled “Bourkeophiles”. No disrespect intended – just a handy term for those that believe in something that violates physical principles. There are numerous examples of this mentality still thriving today and notable examples can be seen on YouTube. The Flat Earth Society, Free Energy, NASA Faked Moon Landings, etc., are actually humorous in a tragic sort of way, in the total disregard for science. I must admit, I get a bit irritated when I hear things like “you engineers don’t know everything – you just know what you learned in college”. To this I must agree, but I learned enough to know that when the physics of mechanics, chemistry or thermodynamics are violated, that’s when I raise the red flag.

Now to relate a couple of Bourkeophile true stories:

I was contacted by a guy who wanted me to do some consulting for him on a revolutionary idea he had for a modified Bourke-cycle. His idea was to use a Bourke engine, raise the compression ratio to a very high value, then inject water into the cylinders at TDC. The high temperature air would instantly cause the injected water to flash into superheated steam, thus propelling the pistons downward with tremendous force. The result would be a steam engine that doesn’t require a boiler and would run on water. I tried to explain that water is not a fuel, heat and work are mutually convertible processes, and rather than adding heat to the compressed air, you would be removing heat and negative work would be generated. Long story short – he didn’t understand and I couldn’t convince him. I didn’t charge for my services which only amounted to a few hours of word salad.

Another guy contacted me on a project that he just knew would be revolutionary and “had to work”! Knowing the virtues of the high power and efficiency of the Bourke engine, he wanted me to calculate the “miles-per-gallon” he could potentially get from a Bourke engine fitted with a 200 mpg carburetor. He was serious and offered an attractive payment for consulting but my ethics prevented it. He actually went away mad after I tried to explain some elementary engine principles to him.

Such is the life of being a consultant in the engine profession.

Dave

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Water injection can be a great idea. Perhaps, down the track now we've got used to the urea tanks, it'd be possible to introduce this? O/T Perhaps an English shorthand for Bourkephiles is Berks... but they may not appreciate the actual derivation.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

BMW has a vehicle with water injection.

https://jalopnik.com/how-the-absurdly-expensive-bm...

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

The OP is nearly a month AWOL, but this has been a fascinating thread. Glad to see it continue.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Quote (ornerynorsk)

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

Great signature line! I used to run an R&D group, and I constantly had to remind leadership "you're focused too much on the D and overly averse to the failure inherent in R"

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Re BMW, water injection, done properly and with full advantage taken on the combustion recipe side, is no less complicated or mission critical than the fuel system and needs to be developed accordingly.
Whereas the fuel system development can be amortized basically across the entire fleet, the water injection system for a niche product is bound to carry a premium cost, if the development cost is borne only by the niche product.
If you doubt my assessment, go develop and validate your own water injection system and let us know how it goes.
That is why, in my view, and history bears this out, that fuel enrichment is the poor man's water injection.
Not to say that water injection isn't better, in principle.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I put my own very crude water injection system on my '79 Mustang. It was not expensive but it did the job of suppressing detonation at elevated turbo boost.

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RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

I've had water injected pulling tractor engines, unfortunately they tended to go boom as they were rather crude. On my hot rods today I prefer to accomplish the same thing with EGR.

RE: The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts!

Like water injection, EGR is a very effective knock suppressant/charge diluent/what have you. Normally, for the same BMEP, you will need more boost pressure with EGR to get the job done versus water injection. This may bring challenges in the air system and power cylinder areas.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

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