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Mydlyfkryzis
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   Posted 12/23/2004 2:01 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Somebody said...
who told you the egine have to be upright it could be flat like a volkswagen aircooled engine that eliminate the high center of gravity..


The Corvette motor is compact. It would be less so as a flat motor ...I.E: Wider. The Engine is small in physical size for it's output.

Somebody said...
theres nothing superior of a push rod engine over a DOHC unless your speakin of simplicity of it, not power wise ..


That's my point, while the OHC motor is "superior" in technology, it is not as well suited for the corvette because it is just physically larger. So being superior technology alone doesn't necessarily make it better.

Somebody said...
i dont want hear about nitro runing engine since thats nothing but a control short lived bomb.


You may not want to hear about it, but the point was that no head gasket 4 stroke engines are an OLD design, not new and the 6 dstroke is not breaking ground with that feasture.

Somebody said...
and also the corvette engine could be a flat motor but that would not go well with the macho V-8 mentality

It also could be a gas turbine engine, which would be more macho than the V8. They had prototypes in the 60's.
While you have a point, it does not have anything to do with the point.- A technology superior engine may not be a better engine.

Somebody said...
you notice the porche 911 still wins tracks .


What's your point here? Porche is stuck on flat engines (for the most part) as much as Corvette is stuck on V-8's. This point still doesn't address my point.


Your refutations of my point have validity, but none of them address the substance of my point.

I think the 6 stroke is a nice exercise in engineering, but probably isn't a really practical idea YET. The web site to me has too many claims without tech back up. For instance, they claim it should have lower emissions. Emissions can be measured. They could compare the prototypes to existing engines and have DATA rather than "it should" statements.

You can keep in mind that a low tech, poppet valve engine, reasonably maintained, outlasts the vehicle its in. A longer lasting engine probably has no "market value" to auto manufacturers as the present product is already reliable enough.
If this is not good enough for you, just keep in mind if the car mfg. can't mfg the old technology with good quality, how will they mfg. new technology with good quality.

My $0.02
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louemc
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   Posted 12/23/2004 2:53 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Mydly, Congratulations, that's some twisted thinking, that can't be easy to come up with.
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Mydlyfkryzis
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   Posted 12/23/2004 6:02 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Not too twisted. Most of it came from a variety of articles I've read recently. I do read some estoric magazines though, not all of it mainstream. Since I am a mechanical engineer, new innovations in engines have a particular interest. I love a good debate on the merits of new technology.

A lot of these issues come up in magazines like ASME's members magazine, TIP (The industrial Physicist), Popular Science, Popular Mechanics, Road and Track, Car and Driver, Autoweek, etc. I just put together some of the ideas that I read about.

A recent article in Road and Track (IIRC the right magazine) discussed why Chevy was sticking with the old Pushrod V8 when Ford and the rest are using OHC designs. The main reason was output per unit size, not displacement, physical size. For a car, a pushrod V8 is the most compact variation of engine designs. The small package and high output for the size package make it an excellent choice.

In addition, what many of these arguments over engine design leave out are econics and suitability. While the 6 stroke may be nifty engineering, it really doesn't pay for an auto mfg to retool its mfg plant for a design that is only marginally better on size or performance . To go to a larger package on an engine, the car chassis itself may need complete retooling. GM in particular has saved a lot a money by polishing the 3800 V8 and 350 V8 and not have to change transmission design (bell housings, input shafts,etc), motor mount design, things like this. To have a compact package of known dimensions allows easier new car design. Not that I am a GM fan, but there are lessons to be learned from them.

When I was going for my masters degree, a number of teams did a whole history of the wankel engine as a project to show how it failed to take over the industry despite many positives about it. Since I work for a large mfg of equipment, I have been privy to discussions about why a new or better technology is not adopted. I used some of the reasoning in mmy debate.

So, not really twisted, everything I stated can be found with a litltle research.

I don't debate over the 'net usually, but some topics are too much fun to resist. :)

Ultimately, though, it is fun even though it doesn't really matter.
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malbeare
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   Posted 12/28/2004 12:06 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
Somebody said...
(6) A one-piece engine from crankshaft to upper shaft becomes feasible. No head gasket
It should be stated that it could now become a common  ecenomicly viable means of manufacture.
 
Somebody said...
(5)The absence of valves within the combustion chamber allows design freedom.
 
the rotary valves are not in the combustion chamber  . A feature of these rotary valves is that they only have to contend with sub atmospheric pressures. They do not physicly touch anything but run within a couple of thou of a boss , do not need lubrication or cooling as they do not deal with exhaust flow but are present to stop the backflow of exhaust during the intake stroke. The exhaust is actually a piston port. The combustion chamber has an upper piston and cylinder sides with the main lower piston on the bottom.
The head hight is exactly the same as the standard Ducati 150mm not taller
Somebody said...
(1)The valving is desmodromic
(2)There are no valves to drop or bounce.
 
The true original greek meaning of desmodromic is driven between tracks. The upper piston is positivly positioned by the scotch yoke crank
 
Somebody said...
(1)The 6-stroke engine is fundamentally superior to the 4- stroke because the head is a net contributor to, and an integral part of the power generation within the engine, unlike a cam only absorbing power.
 
Proof I sujest that you go to the download page and download some of the work done at the uni of adelaide.
Depending on engine configuration the rule of thumb is about 10% superior tourque output for the same compression ratio engine.
 
FUEL CONSUMPTION TEST

ROAD SPEED MPH

4STROKE RUN TIME SECONDS 100cc FUEL

6STROKE RUN TIME SECONDS

100cc FUEL

LOADED RPM

In 5th GEAR

% LONGER RUN TIME

30

159

216

2000

35.8%

35

138

184

2500

33%

40

107

134

3000

25.2%

45

89

101

3500

13%

YAMAHA TT 500cc

Test  by Malcolm Beare, Elliot Munro, Grant Guy, July 1995

The dyno used was an old motorbike dyno with the rear wheel driving a large fan with a speed readout dial. The throttle was opend enough to maintain the designated speed. So the power outputs were  identicle

The sixstroke head was designed to as closely match the fourstroke as possible  compression ratio , valve timing , port sizes. Not a fully optimised sixstroke much more port area is available.

and compression ratio could be higher.

The sixstroke would run happily at lower revs(1000) than the fourstroke in 5th gear.   The fourstroke would pull 4000 RPM at full throttle the sixstroke 3500.

Same gearing same carburetor.

Fuel was gravity fed to the carb from a long clear tube with two level marks to indicate 100cc
 
 
malbeare
 

Post Edited (malbeare) : 3/27/2007 9:51:43 PM GMT

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Mydlyfkryzis
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   Posted 12/28/2004 7:25 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
Just to add to my previous posts, Coates has a rotary valve setup that was patented 10 years ago.

It negates the poppet valve argument from the 6 stroke at any rate....

www.coatesengine.com/

Rotary valves just never to seem to catch on. I suspect the the machining aspect requires more accuracy than auto mfg's want to comply with. Makes the expense of the engine too high. IMHO, of course.
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louemc
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   Posted 12/28/2004 12:40 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Mydly, Thanks for the background, I respect that. I still think the way you have put together "good" facts, have resulted in faulty conclusions though. I'll consider your viewpoint with more "weight", now that I know your background though. Welcome to the site, I value anyone that has something of substance to contribute.
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CaddmannQ
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   Posted 12/28/2004 2:31 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Well, the Beare certainly sounds like a viable alternative, and superior in several ways, but I'm still not convinced about the longevity of the sliding block (Scotch Yoke) joint. The load has got to be rather high near TDC & BDC, while the velocity at 90 before/after jumps way up.

How do you control tolerances, and provide for adjustment? Even at half crank speed, this thing's gotta wear, and once it does you've likely got a real clunker.


Cadd
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Mydlyfkryzis
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   Posted 12/28/2004 3:05 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
That's my take on the rotary valves, too tight a tolerance for easy mass production and materials problems with wear.

The the rotary valve configuration has its pluses, the poppet valve has served very well. Given that it is a simpler to manufacture device and can do the job, I don't see rotary valving taking over the world yet.

My take on it anyway...
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CaddmannQ
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   Posted 12/28/2004 5:06 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
The rotary valve evidently doesn't wear, because it doesn't really have to seal: it runs with a good clearance from other parts.

It just comes around to "chop off" the major gas motion, and then the upper piston comes along to make the positive seal shortly thereafter.


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Mydlyfkryzis
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   Posted 12/28/2004 9:32 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
They alway work new. But it must have some seal effect or you will lose compression. Plus the piston (the valve piston) needs some sealing to do the extra work as claimed on the file.

But still, after 30000 miles and the carbon builds up, I don't know how good it will be.

There are 15000 RPM poppet valve engines (600 honda, for example). I just don't see from an economic sense, the auto mfg's adopting this unless it really does something substantial with emissions too. They really didn't test it for emissions either, so I am suspect about that.
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CaddmannQ
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   Posted 12/29/2004 8:47 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
From what I see, it does not retain compression at all. The upper piston does that. It only acts to baffle reversion.


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Mydlyfkryzis
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   Posted 12/29/2004 9:16 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
Somebody said...
During the compression and expansion strokes, the upper piston seals off both ports, leaving the pressure contained between the two pistons, with the lower one a conventional flat-top three-ring design, while the conical upper one (so shaped to aid gas flow during both inlet and exhaust cycles by guiding it towards the ports) has two rings - one compression, one oil. In the combustion phase,


Rings on both pistons. The "regular" piston of the engine, and the upper, "valve" piston. The rings on the upper piston seal the combustion chaber so the pressure in the cylinder pushes against it, adding 10% of the hp to the engine. Like on a 2 stroke, the upper piston moves and opens ports.

It is like a 2 stroke engine on the head bolted to a 4 stroke on the bottom. Hence the 6 stroke name.

However, to me, from a machining standpoint, I have to build have to build twice as much engine, I.E: a 2 cylinder engine requires the machining of a 4 cylinder.

This is why I believe it will not catch on with manufacturers. It's not because it isn't a "good" idea, only that a mfg wants to simplify construction for cost containment. If this engine had some other positive, for instance, significantly lower emissions or significantly lower weight, it might be worth it. My take is though it supposedly has higher specific output for cubic inch desplacement, it also is a little heavier. It also has a larger form factor. It may have less output than a conventional engine of the same physical size and weight.

So not enough advantage to overcome the drawbacks, to me...
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CaddmannQ
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   Posted 12/29/2004 1:01 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Probably not, but remember that while you add that piston and cylinder, the cylinder is part of the head machining, and you eliminate valves, rockers and pivots, lifter buckets or lifters, valve seats, springs, retainers, clips, and valve guides, seals, and caps; and modern engines have 4 ot 5 of those each per cylinder.


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Mydlyfkryzis
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   Posted 12/30/2004 7:51 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
I tend to agree with you in principle. But I work for a large manufacturer. It is easy to reuse exixting machinery (in the case of the engine, valve/head machinery) than to invest in new machinery. If you notice, most engines share bores, bore centers, etc. Many V-6 are just a V-8 with 2 cyclinders removed. The machinery for valves and heads is already there. Shared across many platforms.

So unless a new technology offers something a manufacturer can't refuse (much lower emissions, much cheaper manufacturing), they are reluctant to change. I didn't read anything on that page that said to me "wow! this is the only way to go".

So while I think it is nifty, and as a gadget freak, I find it interesting, I don't think it has the necessary traits to overcome the existing inertia.

IMHO
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CaddmannQ
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   Posted 12/30/2004 8:47 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
Well according to Beare's chart above, there is a significant increase in fuel economy without reduced power. He posted 13% to 38% but even if it is really only half or a fourth of that Detroit would be jumping through hoops to get it. Do you know what they go through to shave 1% off a car nowadays?

My feeling is that nobody will touch it, not because of the machining costs (remember that the block assy. doesn't really have to change) but because of that damned Scotch Yoke assy.

I just can't see that thing surviving more than 30,000 to 50,000 miles without an overhaul. Look at what minimal movement and surface a piston pin entails, and then compare it to that Scotch Yoke sliding block/pin/track/upper crank as an assembly.

There's gotta be bushings or needles, plus retainers, and thrust compensation, but how do you deal with the sliding block-to-track tolerances? They're going to be tight if you don't want a clunker and need accurate timing, but have to be loose enough to allow heat expansion. And they must be pressure lubed for longevity, but where does the expelled oil go? Out the ports? That part would be an economic & pollution nightmare! Perhaps advanced ceramic-composite technology could solve all that but now you're really talking a deal breaker for the manufacturer.

Evidently they are keeping this engine together long enough to run races, but could it live as a production engine, have a life of 100,000 to 200,000 miles, and control pollution?


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GeoffG
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   Posted 12/30/2004 10:07 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
Cadd, what Scotch Yoke are you referring to? I understood that the upper pistons are carried on a crank, just like the main crankshaft, just with a much shorter throw. Why would anyone try to carry them any other way?

Personally, I think that while this is a good idea, it is really just another way of getting gases into and out of the cylinder. I'm more interested in things like direct fuel injection for gasoline engines, to increase mileage and performance. This technology is already being used on, of all things, two-stroke outboard boat engines (cleans up the 2-stroke exhaust enough to get them past emissions testing...). Many of the efficiency advantages of diesel engines are directly related to their use of direct injection.
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CaddmannQ
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   Posted 12/30/2004 10:37 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
The upper piston is driven by a crank, whose crankpin carries a square block of metal, which slides in a horizontal slot in the upper piston. It provides motion to the upper piston without a connecting rod.

Mathematically it makes sense, but in practical terms I feel it would be short lived, even at half the main crank speed.


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Mydlyfkryzis
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   Posted 1/1/2005 9:44 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Caddmannq said...
Well according to Beare's chart above, there is a significant increase in fuel economy without reduced power. He posted 13% to 38% but even if it is really only half or a fourth of that Detroit would be jumping through hoops to get it. Do you know what they go through to shave 1% off a car nowadays?


If the economy was true, I would agree, but this is a claim, rather than a certainty:

From Articles at Beare Website said...
Malcolm Beare claims his engine is 35% more economical at low revs/throttle openings than an equivalent conventional engine and 13% less thirsty at high rpm/full throttle, in spite of the doubled-up carbs. That should mean fewer hydrocarbon and CO2 emissions


He may be right in some sense. However, it is a "larger" physical engine. The complexity of the head in a multicyclinder engine is much greater than on the single cylinder (or V twin, which to me, is 2 singles). The engine is not a compact engine. A V-6 with this head would be a few inches taller than present and if my car is any indication, there isn't enough room for the engine that's in there.

To much Speculation, too much new machinery, some drawbacks.

For a special application, Drones, light aircraft, snowmobiles, some motorcycles, It may be feasible and even desireable. But I still don't see it mainstreaming in time for me to experience it. Heck, by the time this takes off, if it could, there may be a whole 'nother, better technology, something with flux capacitors or something burger

You are also right about the scotch yoke. I think there may be better ways or variations on this to give a better result...

MY $0.02
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malbeare
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   Posted 1/2/2005 12:26 AM (GMT -7)    Quote This PostAlert An Admin About This Post.

"He may be right in some sense. However, it is a "larger" physical engine. The complexity of the head in a multicyclinder engine is much greater than on the single cylinder (or V twin, which to me, is 2 singles). The engine is not a compact engine. A V-6 with this head would be a few inches taller than present and if my car is any indication, there isn't enough room for the engine that's in there."
 
The cylinder head is the same height as the original OHC engine 150mm, so what is the head height of the V6 from  head gasket to the top of the rocker cover? . I have just measured my old Datsun 1500 pushrod OHV and it is 180mm, add 20 mm for the filler cap.
We have an air assisted injector that produces an average of 5 micron fuel particle size and induces 20% air premix.We use a standard injector pluged into our nozzle. It is going to be situated in front of the reed valve to inject directly into the cylinder through a lovely big open port. But the injector is protected from combustion by the upper piston.Direct injection without the problems of wall wetting and carbonned up hot high pressure injector.
 
All of my prototype so far have been produced by seat of the pants engineering and intuition. We know that a manufacturer would like to see a fully finished all sorted inline 4  that FEV or Ricardo have had a hand in,with costings and existing plant utilisation.But that takes capital that we are trying to source.Perhaps as a project engine several manufacturers could help fund this and share the costs .
Thankyou for indicating that this is neccessary.
I have tried several methods of driving the upper piston, conrods up and down but that imparted less desirable motions to the upper piston and added height and weight.The design as is is slightly less weight than the standard head as there is less steel and obout the same alluminium.
The upper piston has oil controll rings that stay above the ports to keep the oil in the upper piston cavity. Yes it is pressure fed and extracted.
Malbeare
 



 

Post Edited (malbeare) : 3/27/2007 9:52:44 PM GMT

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malbeare
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   Posted 1/2/2005 1:51 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
I think that the scotch yoke drive strength and durability is a simple matter of good engineering to achieve a long life, after all the original cam has to bear simmilar loads, about 10% of engine power absorbed, with only line of contact and not a proper spread that a bearing or sliding block gives.
The load on the block is virtually only in one direction that is upwards with compression and expansion and then driving down against ring tension until the ports are closed.
Malbeare
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CaddmannQ
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   Posted 1/2/2005 11:04 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
The typical cam has the advantage of adjustable rockers, interchangable bucket shims, or hydraulic lifters. As wear occurs it can be compensated for.

Getting inside the upper piston to make adjustments seems improbable without a teardown, so perhaps a hydraulic sliding block might eliminate the necessity.

Or, perhaps some advanced metalurgy could prove the answer.

I'd be interested to know just how many hours have been successfully put on any Beare engine, and what the failure points or prime wear points were.


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GeoffG
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   Posted 1/2/2005 4:27 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
malbeare said...
We have an air assisted injector that produces an average of 5 micron fuel particle size and induces 20% air premix.We use a standard injector pluged into our nozzle. It is going to be situated in front of the reed valve to inject directly into the cylinder through a lovely big open port. But the injector is protected from combustion by the upper piston.Direct injection without the problems of wall wetting and carbonned up hot high pressure injector.

When I said "direct injection" I was referring to injection of atomised fuel directly into the cylinder near the end of the compression stroke (like a Diesel engine), not injected into the intake flow. This allows for higher compression to be achieved without pre-ignition, as I understand it.
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malbeare
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   Posted 1/6/2005 1:49 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
Mydlyfkryzi said

 

 
 

For a special application, Drones, light aircraft, snowmobiles, some motorcycles, It may be feasible and even desireable.

MY $0.02
The best possible special purpose is a motoGP bike

To help keep a cap on power and, hence, speed, the MSMA has decided to propose a reduction in engine capacity from 990cc to 900cc. "The intention is not to reduce performance but to prevent a continuous improvement in speed and lap times," according to the press release.

2004 2007 weight changes
2 Cylinders 135 Kg 133Kg - -2Kg
3 Cylinders 135Kg 140.5 Kg +5.5Kg
4 cylinders 145 Kg 148Kg + 3Kg
5 cylinders 145Kg 155.5 Kg +10.5 Kg
6 cylinders 155Kg 163 Kg +8Kg






The proposed changes to the rules also affect the minimum weight standards, adding more weight to engines with more than two cylinders from 2007.


The proposed changes above may indicate the technical direction that some manufacturers are pursuing for the future. As Honda is the most powerful voice among the companies, it is interesting that the proposed minimum weight for five-cylinder machines, such as the Honda RC211V (and Proton KRV5), has been increased the greatest amount. This may indicate that Big Red is already working on new engine configurations and is looking to abandon the V-5.

And, as two-cylinder bikes are the only ones to get a minimum weight decrease, might we see the introduction of a 900cc MotoGP V-Twin? If so, it wouldn't be as powerful, no doubt, but it would enjoy nearly a 50-pound weight advantage over a V-5-powered machine. And, as a Twin would have a 66-pound advantage over a six-cylinder-powered bike, it looks like the rumors of a Honda V-6 will not be fulfilled.

The MSMA is also looking at perhaps reducing the 2005 rule for a 22-liter fuel tank capacity (down 2 liters from current rules) for the 2007 season.

The introduction of 4-stroke machines to MotoGP has resulted in a huge amount of newfound interest in the class. Now, with revised regulations again on the table, the series might get even more interesting.


The Testastretta engine fitted to the Ducati 998R 2002 version, the bore is 104 mm.
Unfortunately, such a large bore currently causes combustion problems with dramatically decreased efficiency.
This stems fundamentally from the need to augment the injection advance and from the worsening of the "shape factor" of the combustion chamber which, with the reduction of the bore/stroke ratio, becomes ever broader and flatter. The "shape factor" is a critical synthetic value to check a combustion chamber's good operation, and a good indicator of its compactness and "thermal efficiency".
It should be borne in mind that aspirated racing engines require rather extreme valve lift and overlap angles, therefore, cavities are made in the piston crowns to prevent contact with the half-open valves. The combustion chamber is therefore practically contained in the piston cavities, such cavities becoming bigger as the stroke/bore ratio decreases, which makes it hard to obtain the high compression ratios required by high specific power engines.

The Beare sixstroke does not have these limitations because the main lower piston does not have valve cutouts and the combustion chamber is a compact design with squish contribution from both upper and lower pistons. The shape is much more like a fist than a flat hand hence thermal efficiency is high .
Combustion chamber diameter oprox 75mm
The main piston is lighter and stronger than the 4-stroke, because the lack of cutouts allow a thinner slightly domed top
.
Malcolm does believe that the sixstroke 15kg weight advantage will be a major benefit for the Beare Sixstroke, much more so than the 30kg handicap enjoyed by Twins in 500cc twostroke racing. "Working on the assumption that all these four-strokes are going to make enough horsepower, 15 kilos is a lot," he says. It’s straightforward enough, the Twins will have a 10 percent weight advantage and force equals mass times acceleration, so it is a big difference.


Sixstroke Beare 900cc Vtwin MOTO GP

Bore 116.25 mm stroke 42.5 upper bore 82mm upper stroke 34mm
compression ratio 12.25 to 1
power 337HP @ 15000 RPM
torque 74.6Ft/Lbs x80% x2 = 118Ft /Lbs
piston speed at 18000 is 5019 Ft/min or 25.4965 Mtre / sec
XL engine file
Torque 101.2 NM or 74.6 Ft /Lbs discount by 20% and multiply by 2 for twin cylinder is 118 FT/ Lbs
6 port design with 3 exhaust ports leading to a rotary disk, 3 intake ports,One intake rotary disk and 2 reed valves with air assisted injectors. 2 or 4 10mm plugs per cylinder.
The port area is oprox 20% to 30% more than a 4 valve head
Results of XL file sixstroke touque calculator

        Based on Dual Cycle               
                Total Torque       
Fourstroke        62.00       
                       
Main        Top               
66.05        35.15        101.20       
                       
Increase in torque                63.23%        
                       
http://www.sixstroke.com


Malbeare

 

Post Edited (malbeare) : 3/27/2007 9:53:28 PM GMT

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Smax
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   Posted 1/13/2005 12:41 AM (GMT -7)    Quote This PostAlert An Admin About This Post.
Malbeare:  if you're still out there, I found a short 'bio' and road test of your 6-stroke Ducati by Alan Cathcart from 1999 and was quite impressed by your 'bush-engineering' - anyone with Ian Drysdale's support must be on the right track!
 
Good luck in the development of your projects. lol  


 If I have to 'understand', please don't try to explain...

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malbeare
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   Posted 1/17/2005 7:30 PM (GMT -7)    Quote This PostAlert An Admin About This Post.
Smax,
 Thankyou for your kind comments
smilewinkgrin 
http://www.sixstroke.com

Malbeare

 A tidy mind is not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway

 

Engine Cutaway

Post Edited (malbeare) : 3/27/2007 9:54:23 PM GMT

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