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sixstroke engine

sixstroke engine

sixstroke engine

(OP)
Please tell me what you think.

Sixstroke a new head design for 4-strokes                  
             
(1)The Sixstroke engine is fundamentally superior to the 4
    stroke because the head is no  longer parasitic but is a  net contributor to, and an integral part of  the power generation within the engine.                             
(2)The 6stroke is thermodynamically more efficient because  the change in volume of the  power stroke is greater  than  the intake, compression, & exhaust strokes.                             
(3)The compression ratio can be increased because of the    absence of hot spots.                      
(4)The rate of change in  volume during the critical combustion period is less than in a 4stroke.                       
(5)The absence of valves within the combustion chamber     allows design freedom.                      
(6) A one-piece engine from crankshaft to upper shaft becomes feasible. No head gasket.                        

The engine has proven to be robust on the race track, & have significant  advantages over 4-strokes                       
(1)The valving is desmodromic                       
(2)There are no valves to drop or bounce.                       
(3)The rev limit is only what the bottom end can stand.              
   (4)Gas flow on intake increase of 20%.                       
(5)No possibility of engine damage if the timing belt slips or snaps                       
(6)The reed valves are so close to the intake ports that their tips become the virtual port opening. This achieves   variable port area & variable engine demand valve           
timing. The tips open late & small amounts with   low       throttle settings & open early & fully at full throttle         
To check this out visit my site at                                                 
       
    www.sixstroke.com ;         
                   
 regards Malcolm Beare  

RE: sixstroke engine

Try www.dynobike.com

They have a book outlining the Beare engine.  
I have seen the kit; and have been told by friends who have seen the bike that it is a very good inovation and with proper PR should make it.  We shall see, a lot of 'great inovations' didn't 'make it'!


Rod

RE: sixstroke engine

I'm waiting patiently to see some documented "six stroke" high rpm perforformance numbers/tests.  Alan Cathcart said that M. Beare was quite crafty....But rod,let's hear about YOUR "great inovations".

RE: sixstroke engine

(OP)
stroker,
at this stage of developmentthe performance of the prototype is ahead of the conventional engine up to 6500 RPM, therafter the power takes a nosedive.
the reasons for this are many and my resorces do not alow rapid development.
the reed valves could be fluttering above 6500.
The timings are still conservative.
The intake port direction aranged in a loop scavenge could be wrong for this concept , a complimentary swirl might be better.
Rotary disk valves on the intake instead of or as well as reed valves should allow better higher RPM poer output.
  The following is some of my thoughts for the F1 motorcycle.



The other benefit is that the cost of manufacture would be lower because per
cylinder the BEARE Sixstroke head has 15 parts and a 4 valve single overhead
cam head has between 35 & 50 parts depending on design.

I would dearly like to build a motor for the new F1 formula for motorcycles
to be implemented in 2002
4 stroke engines of more that 3 cylinders of a capacity of 990cc.
If there is any company interested in pursuing this I would certainly like
to hear from them.
I would take a Honda 1100 V4 as the base motor build a new shorter stroke
crankshaft and add my head design.
90 deg V flat crank with a central gear train to the heads. Reed blocks on
the outside of the V so that their intake runners are longer for the low
speed high torque tuning. They run from the top of the V over the heads
tapering from a diameter of about 50mm to about 35mm at the reed blocks.
Rotary disk intakes on the inside of the V with short runners about 40mm
diameter for the high revv tuning. Rotary exhaust disks are on the ends of
the motor, so heat build up in the centre of the motor is not a problem.
. Per cylinder the intake valving will consist of one reed block (8 petal)
and a rotary disk valve. The reed block will have the same gas flow as a
conventional 4 valve head but will have conservative timing. The reed block
will feed 3 ports angled at an offset to produce a good swirl. The reed
valves are so close to the intake ports that their tips become the virtual
port opening. This achieves variable port area & variable engine demand
valve timing.  The tips open late & small amounts with low throttle settings
& open early & fully at full throttle.
The rotary disk will have the same gas flow as a conventional 2 valve head.
It will be aimed straight in but angled down, and will have more radical
timing than the reed block ports. The aim is to have a combined gas flow
about 15% to 20% better than a 4 or 5 valve head. At low to medium revs up
to about 6000 rpm only the reed block controlling butterfly is operational.
This butterfly being directly connected to the throttle grip and having a
throttle position sensor on it. The rotary valve-controlling butterfly is
controlled by a servomotor and after 6000 rpm it is ramped open with a time
delay of a second or so to the same throttle position as the reed block
butterfly. Then above 6000 rpm it follows the same positioning as the reed
block butterfly. But shuts down below that figure.  By this configuration
the engine should have a very good torque spread and still have exceptional
high-end power.  The motor will have two injectors per cylinder, one aimed
at the back of the reed block and the other upstream of the rotary valve
butterfly. The reed block injector is operating all of the time and the
second one whenever the rotary valve butterfly opens.
Another radical feature is that the main cylinder wet sleave will be
integral with the head. There will still be a water jacket gasket but no
combustion chamber head gasket. This is very good for heat paths throughout
the engine and eliminates any combustion leakage. Both the upper and the
lower main cylinder will be nicosil. The combustion chamber will be
basically bell or conical shaped with 3 spark plugs.  Three spark plugs will
allow a very short flame path and not much ignition advance will be needed.
Hence the pistons will not be doing as much negative work fighting
combustion.
 The head is a 5 port head, one wide exhaust port, 3 reed block ports and
one intake rotary disk port per cylinder.
. So we have an engine with 3 crankshafts, 8 pistons 4 large & 4 smaller,
4-reed block & 4-disk valve intake, 4-disk valve exhaust. 12 spark plugs, 8
injectors. The valving is not subject to cylinder pressure. The upper piston
does all the high-pressure sealing. At TDC at the end of the exhaust stroke
and the beginning of the intake stroke all of the ports are fully open. This
enables the use of exhaust extraction to get the intake moving sooner and
faster than conventional valving where the valves have to be nearly closed
in order not to hit the piston.


RE: sixstroke engine

Happy New Year Beare! Do you have any info up on the web?...Like plots of "6stroke" hp,torque,bsfc,bsac,etc. Is your site working?

RE: sixstroke engine

Well stroker, I made it to retirement.  For someone with my chosen lifestyle, that's 'inovation' enough for me.


Rod

RE: sixstroke engine

rod, Retired you say!  Well,Congratulations ol' boy! Darn, and I've still got 33 years to go!

RE: sixstroke engine

stroker---Post a bio for us so we can look over your  'bona-fides'.  And like I said, click on any of our names and read our bios.  Lots of very good people here. Welcome.


Rod

RE: sixstroke engine

rod,Thanks! I'll put some info in my profile section. But I clicked on your bio and you have no name...

RE: sixstroke engine

Most use no name in these forums, in keeping with the original idea of annonimity .  If you have a specific, personal wish you may e mail me.  Often names and address will be deleted by the folks who run these forums.  

Rod

RE: sixstroke engine

Dear Mal Beare = I have been all over your impressive site back the preceding year. We both need the same amount of luck.  I like your VF 1100 ReDuxScheme. The biggest flaw concerns CoG Masses and crank center-line pushing the weight away from the front wheel due to the tall cylinder-heads which is an L-twin attribute like your proposed Hondacati. There was another Honda V4 1000 in the Mid-80's with the Interceptor architecture where the whole profile is tilted back more for the crank to move forward and the F-tire weight to improve. I have an old VF-1100 SabreRat that still eats tires, that your welcome to utilize for machination.  I have to  wonder what terminal RPM you envision with this configuration; if your concerned to achieve max vehicle velocity like a pnuematic set-up, or are you designing to simply torque around a short twisty track to victory. Seems to me, in this arena you need to create max torque from idle and then be able to turn 25K rpm for velocity in any of the rules required 6 gears. If you look at the rules your V4 scheme would be more efficiently simplified by configuring as a 'shared' combustion chamber set-up ( very vaguely like the old Garrelli/Puch twingles) that was written-in to anticipate the variations on the oval-pistoni mind-set. Henk Cloostermans' "Desmodromology" Book/Site covers some progenators of your 6Revolver from the 20's I believe. This lacked the Scotch-yoke upper(conventional) crank and used individual pistons as I/E valves. Did you ever see the Speed-Record Vespa from way-back with the pistontopiston siamese twin that shared a ring combustion chamber. There was a sub-marine diesel that did this too,and later used as a locomotive power-plant. What are your thoughts on the New 50cc Piaggio EV-2? that uses the little pre-compression piston over-head. Kinda similar? Your best bet is to think 'Stratified' for a sexy commercial application. When you get a chance, go check-out my "DesmoNova" NET-Site, and make a little more room in the dinghy for me too. Cheers, Terry Linebarger

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