×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

9 cyl. radial motorcycle picture

9 cyl. radial motorcycle picture

RE: 9 cyl. radial motorcycle picture

I always wanted to put a 5 cyl in the wheel

where would you use it?

RE: 9 cyl. radial motorcycle picture

On straight flat roads!

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: 9 cyl. radial motorcycle picture

Oh, well OK, straight roads.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: 9 cyl. radial motorcycle picture

I would sure hope it didn't drop a rocker arm and spit a push rod out the top.

It might be a good idea to only ride it with emergency services close by, but then again, there might not be much left for them to do.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

RE: 9 cyl. radial motorcycle picture

I count seven cylinders.

Mike Halloran
Pembroke Pines, FL, USA

RE: 9 cyl. radial motorcycle picture

(OP)
Slightly less than the 180 degrees of the "top" half of the circle contains contains 4 complete cylinders.
Double  plus 1  =  9.
 

RE: 9 cyl. radial motorcycle picture

I stand corrected.  

I didn't know they made nines that small.

Going 'up' in the URL gives me information on fiberscopes, with no link to the motorcycle.  Anyone know more about it?

Mike Halloran
Pembroke Pines, FL, USA

RE: 9 cyl. radial motorcycle picture

Rotec are only about five minutes away from me here, I might wander around and have a look.

RE: 9 cyl. radial motorcycle picture

Thundair, Sorry to spoil the concept but putting a radial five in the wheel has been done already!
The front wheel as well!

Cheers , Pete.

RE: 9 cyl. radial motorcycle picture

Ok, my turn to be stupid:  (please hold your comments!)
Why are all radial engines odd numbered?

Franz

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

RE: 9 cyl. radial motorcycle picture

Not being an automotive design guy in any shape or form, my first guess... does it have anything to do with directly opposing cylinders firing at the same time being a bad thing?

Dan - Owner
http://www.Hi-TecDesigns.com

RE: 9 cyl. radial motorcycle picture

That is a very interesting question. All the cylinders (effectively) operate off a single crankpin. So all the cylinders must fire in sequence around the engine. But each cylinder only fires every other revolution.

I guess the firing sequence would be something like 1-3-5-7-9-2-4-6-8. Every second cylinder in sequence fires around the engine. Pairs of side by side cylinders would reach TDC almost simultaneously. one would be at TDC firing, and the other at TDC overlap. That sort of sequence only works with odd numbers of cylinders.     

RE: 9 cyl. radial motorcycle picture

Imagine the work in assembling something like that.

RE: 9 cyl. radial motorcycle picture

MOST radial piston engines have an odd number of cylinders per crankpin because they are four- strokes, and commonly use a shared cam ring running at half output speed to actuate the valves on all cylinders.  With a little mental gyration, you can eventually come to the understanding that there must be an even number of cylinders, or you run out of cylinders after one cam revolution.

It is not accurate to say that ALL radial four strokes must have an odd number of cylinders per row.  I am aware of two exceptions, both produced early in the 20th Century.  The Fairchild- Caminez had four cylinders, and the Marchetti had eight.  I think the Fairchild- Caminez was produced in some quantity, and there may have been variants.  The Marchetti was produced not by the Italian airplane manufacturer, but by Paul Marchetti of San Francisco, who died while flight testing an airframe in which to flight test his engine.  

I got interested when I saw a photo of what must be the Marchetti engine, sitting alone somewhere, in some technical fish wrapper, with a derisive caption about how stupid you had to be to actually build a radial eight.

I can't remember which fish wrapper, but I did find images from Paul's advertising campaign, which you can probably Google up.  

...

There is a trick, of course.  Both those odd engines use sturdy desmodromic cams and rockers to actuate the pistons.  There is no crankpin.  Each cylinder does a complete cycle in one output revolution, so the 'crank cams' are symmetrical and naturally balanced.

Mike Halloran
Pembroke Pines, FL, USA

RE: 9 cyl. radial motorcycle picture


Refined radial engines have an odd number of cylinders to allow for a constant every-other-piston firing order. A 7 cylinder fires 1-3-5-7-2-4-6-1...

An even number of cylinders can't do that.

Not sure about the 4 layered version smile.


RE: 9 cyl. radial motorcycle picture

There is a 8 cylinder radial 2 stroke diesel for the kit plane industry by Zoche in Germany.  http://www.zoche.de/specs.html  
It uses a supercharger and a turbocharger and uses a compressed air bottle as a starter when it dumps air into the direct drive supercharger to turn the engine over to start it.

_____________________________________
I have been called "A storehouse of worthless information" many times.

RE: 9 cyl. radial motorcycle picture

That bike has to sound cool as hell when they start it! I just hope it's not a kick start. Not to mention all the smoke it must belch out! I would recommend a belt guard be installed.

Scott

In a hundred years, it isn't going to matter anyway.

RE: 9 cyl. radial motorcycle picture

An interesting read on radial and aircraft engine design is W.O. Bently's auto biography. It is long out of print but you can find it used. It also talks about his cars and his entire career.

The best story is where some American auto executive is telling him that the problem with his company that the engineers have to much power and that the accountants should be in control. He didn't realise that Bently was an engineer. The irony is that in the end the accounts did take over the company.

RE: 9 cyl. radial motorcycle picture

One particularly interesting application of a radial engine was the very first Sherman M4 tank.

This had a 400 Hp air cooled radial engine that sat right behind the driver and tank commander. Their heads were only about a foot in front of those rather large finned cylinder barrels. The gearbox was between driver and commander at hip level, and it drove the tracks from the front.

I often wondered about the heat and noise, especially in the tropics with the hatches shut. Later versions of the Sherman used a diesel engine.

RE: 9 cyl. radial motorcycle picture

A long time ago, I crawled up on what I think was a Sherman in an armory's back lot and opened the engine hatch.  The engine was big, clearly air cooled, and I think maybe a V12.  I don't know what it used for fuel.

Mike Halloran
Pembroke Pines, FL, USA

RE: 9 cyl. radial motorcycle picture

The Sherman seems to have used a whole range of different production engines at different times. Some may even have been fitted with non standard engines.

http://en.wikipedia.org/wiki/Sherman_tank

Right at the end there is a list of engines used.

There is an early fully restored M4 Sherman at a tank museum here in Melbourne.  They also had some engine parts on display, including a radial that had blown up. Apparently the master connecting rod had failed, and all the other connecting rods were twisted into unbelievable shapes, quite a sight.

RE: 9 cyl. radial motorcycle picture

At the museum in Harlingen Texas, there is what I think is a Sherman on display but it may be some other WWII motorized implement.  I looked in the engine hatch and saw what I think is 4 or 5 flathead engines joined by a common crankcase (arranged in a radial formation!) with what I assume is some sort of spur gear setup on the drive end.  It may have been Cadillac flathead V-8's.  With the exception of the top one, the others were arranged in some inverted fashion.  Cool!

Franz

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

RE: 9 cyl. radial motorcycle picture

I recall seeing a picture in a book a very long time ago which sounds like that same engine.

This was a four row radial engine of five cylinders (20 cylinders altogether) and it used standard production flathead V8 crank, pistons, rods and cylinder heads.

Only the block was special. Almost everything else came straight off existing wartime production lines. As I recall from the article, this engine was developed at very short notice during WW2 as a tank engine, and was only made in very small numbers.

RE: 9 cyl. radial motorcycle picture

I think you'll find (code for, I checked and...) it was used in 7500 M4A4 Shermans. That's roughly 20% of total production. It was called the Chrysler A57.

The engine was a lot bigger than the earlier ones so the hull was made longer to accomodate it.

The (Australian) Sentinel used a similar arrangement of 3 V8s, because V8s RULE.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: 9 cyl. radial motorcycle picture


Looks like 5 engines simply stuck together on a common circle. Lower 2 banks laid almost flat and were at different spacing to those above. Must have been a real gas hog.

RE: 9 cyl. radial motorcycle picture

R-680 Lycoming, I believe.

680 cu.in. 300 hp @ ~2100 rpm

They where one engine option for a Stinson Reliant.
I flew one so equiped in the 60's, an oldy-but-goody even then. Very smooth.

But in a motorcycle? I only believes it cuz I sees it.

RE: 9 cyl. radial motorcycle picture

Re: the tank engines.

They were quite common, called "tank engines" and available surplus for many years after the war. They were Continental W-670's, 7 cylinder, rated 225 hp. Used often by crop dusters. (why overhaul? just get another tank engine)

On gasoline fueled armor:
Pilot sometimes called the Betty Bomber "the flying Zippo" - a few hits and in was burning. In turn, the Germans called our Sherman tank "the Ronson" for the same reason. A gasoline powered tank is easy to light.

RE: 9 cyl. radial motorcycle picture

The Spruce Goose had eight (8) "Corn Cob" engines. Pratt-Whitney's, Seven rows of 5 cyl. Very complex engine.
It's still the largest sea plane ever built.

Best regards
pennpoint

RE: 9 cyl. radial motorcycle picture


I think the Herculese (Spruce Goose) used the 28 cylinder Wasp Major pictured above. Check out the link above the picture.

RE: 9 cyl. radial motorcycle picture

Fabrico is correct.

Howard Hughes used Pratt & Whitney R-4360's to power the "Spruce Goose". They were the early "high tension" ignition model engines and had severe engine miss fire at altitude. This was cured by what was called the "low tension" ignition configuration later on in the R-4360 development.

I was a USAF reciprocating engine mechanic during the Viet Nam war. My first few years were spent working on R-4360's as installed on Douglas C-124 aircraft. The flight engineers panel had four osciloscopes. One for each engine ignition. Also, the engines had torque meters built into the nose case. Another item for the flight engineer to monitor on take-off.

Being behind one of these engines on a test stand during "military takeoff power" was, well, unreal to say the least.

A very few Chance-Vaught F4U (Corsair) fighters (WW II) were engined with R-4360's. If I remember correctly, the pilot had to take off with the tail wheel down for prop clearance. Landing, ditto. Also, the torque was so severe that take off was extremely------EXCITING!

The F4U with R-2800, R3350 (Wright 18 cylinder) and especially with a R-4360 were the air superiority fighter of WW II. I know several pilots who flew F4U's in combat in the Pacific. They have great stories about these radial powered machines.    

RE: 9 cyl. radial motorcycle picture

Fabrico
WilliamH
I stand corrected
Thank you

Best regards
pennpoint

RE: 9 cyl. radial motorcycle picture

At one of the older Texas Confedrate Air Shows, one of the only flying B-29's lost a jug during takeoff but completed the show with a feathered prop.
When they landed, a crowd gathered around as the techs pulled the cowling, located the bad jug and piston and replaced same.  I seem to remember it being somewhere in the middle of the stack, facing the engine about the 9'oclock position, plus seeing more safety wire, nuts, clips, and shielding I have ever seen.  Air cooled engines have an advantage on engine repair without draining coolant.
The process took about 4 hours, certainly not war-time speed, but no one was shooting at you either!

Franz

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

RE: 9 cyl. radial motorcycle picture

I saw that plane in the early 1990's when it was on tour. Very impressive.

RE: 9 cyl. radial motorcycle picture

If I may regress temporarily, Mike Halloran is right, the motorcycle is a 7-cylinder.  A line splitting one cylinder in half and extending through the shaft center leaves 3-1/2 cylinders within 180 degrees; 3-1/2 x 2 = 7.

The neatest radial that I have seen was a comparatively minute 5-cylinder, vertical shaft, on what appeared to be a portable military generator set.  I couldn't help but think of what a fascinating way to accomplish what could surely have been done more inexpensively with a single or twin Briggs and Stratton.  Only in the military!

I suppose that that configuration (5-cylinder, vertical shaft) would be the only way to have an even firing, inherently balanced 5-cylinder automobile engine.  It could feed directly into a front (or rear) drive transaxle.

RE: 9 cyl. radial motorcycle picture

I wonder if this radial configuration can be optimized to be fuel efficient.

RE: 9 cyl. radial motorcycle picture

Re the Sherman tank engine shown by Fabrico 30 May 06 15:49

Looks like 6 plug wires leaving each distributor, so probably an Sherman M4A4, with a radial arrangement of 5 straight-6 Chrysler A57 engines (Wikipedia mentions selected models, so perhaps others).  Also, the M4A4 cutaway diagram shows this was water-cooled.

RE: 9 cyl. radial motorcycle picture

HI FOLKS - SAW THAT INTERESTING 30 CYL ENG. -   IT IS A DODGE / CHRYSLER 6 S.V. CAR ENGINE - MOUNTED AS FABRICO SAID IN A RADIAL LAYOUT - POWERED SHERMAN TANKS ALSO -  J.C. - CAN'T READ ALL OF THIS PANEL RIGHT HAND HALF OFF TO RIGHT ON MY SCREEN IF ANYONE KNOWS HOT TO FIX THAT PLS SAY SO - HAVE SHOT OF IT - THANX FOLKS J.C.

RE: 9 cyl. radial motorcycle picture

jcai,
Is your display set at 800x600? Try 1024x768 and let us know if it works, so can tell Dave.
Ken

RE: 9 cyl. radial motorcycle picture

You should be able to scroll to the right.
Apologies to anyone who gets messed up by the wide picture of the radial. (I try never to go over about 650 wide!)

RE: 9 cyl. radial motorcycle picture

HI FOLKS - RESET SCREEN TO 1024 X 768  - RESULT VERY TINY LTR - DIFFICULT FOR OLD J.C. TO READ - DID NOT SOLVE PROBLEM OF 40 % OF THIS PANEL BEING TO THE RIGHT + OBSCURED - NO RIGHT / LEFT ARROWS ON SCREEN SO CANT SCROLL LEFT OR RIGHT - JUST ANOTHER DUMB OLD AIRPLANE ENGINEER THANKS FOR YR HELP - THIS DOES NOT HAPPEN ON SOME OTHER SECTIONS OF THIS WEBSITE - WEIRD - HAVE NEW WINDOW XP PRO  - FII BUTTON DOES NOT HELP - SORRY BOUT SPELLING CANT SEE TO CORRECT IT - J.C.

RE: 9 cyl. radial motorcycle picture

jcai,
Eng-Tips lacks a bottom scroll bar when needed for wide photos.
For larger letters, go to Display Settings, Advanced, then switch the screen font size from small to large  (125%).  Hope it works,
Ken

RE: 9 cyl. radial motorcycle picture

THANX KEN - THE PROBLEM IS THAT 40 % OF THE PAGE IS OFF THE SCREEN TO THE RIGHT - THANX ANYHOW - J.C.

RE: 9 cyl. radial motorcycle picture

Might be a simple fix - mine was the same and I am on Windows Internet Explorer browser - my left side favorites bar was too wide pushing the right of the web page off screen.  Just place the curser over the border between the open website and that bar, click and drag it over  - hope that helps

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources