Not a 2-stroke I think but a very clever piece of German kit.
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Forum whore
Not a 2-stroke I think but a very clever piece of German kit.
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In the riders seat
http://www.pivotalengine.com/Originally Posted by TZ350
Thats been around for a while I remember seeing it at Ruapuna on display at at Race meeting quite some time ago
I see it says 02 on one part of the site
"If you can make black marks on a straight from the time you turn out of a corner until the braking point of the next turn, then you have enough power."
Forum whore
The Two-Stroke Shop
Stephen Rothwell and Wayne Wright (Wobbly)
www.twostrokeshop.com
Email: info@twostrokeshop.com
THE most advanced high-performance two-stroke motorcycle engine on the market today.
http://www.twostrokeshop.com/two_str...op_engines.htm
Toroidal head and flat top piston.
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Forum whore
Did they have it running? I see the power output is not that high. Still clever stuff though.
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Forum whore
The effects of higher compression ratios in a 2-stroke:-
http://www.vintagesleds.com/library/...ompression.pdf
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Forum whore
"You may be interested to know, that in many cases a non-squish combustion chamber, with its complete utilization of the mixture to offset the power-limiting effects of a necessarily-lower compression ratio, has proven to be best in absolute terms of power and economy."
Read it all here:- http://toostroke.blogspot.com/2007/12/squish-bands.html
"Our application here, of course, is strongly biased toward maximum horsepower, and that points toward a squish-band head - which is what you will have in most motorcycles in any case. I will warn you, now, that it may be unwise to follow the old-time tuner's habit of increasing an engine's compression ratio as an opening gambit in the quest for better performance. Indeed, before your work is done you may find it necessary to reduce your engine's compression ratio below the stock specification. You see, in the final analysis it is not so much compression ratio as combustion chamber pressure that determines the limit - and these are not at all the same things."
It looks like combustion chamber shape can be a trade off between broad power and maximum horsepower.
As team ESE is running basicaly identical Suzuki GP125 engines except for combustion chamber shape it will be interesting to see how this plays out over the next few dyno runs at Henderson Yamaha.
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Forum whore
A cataloge search engine of all things!!!!!!
Lots of 2-stroke piston stuff. Probably can find rod-kits and other bucket stuff if you look.
http://www.who-sells-it.com/r/mahle-...-2-stroke.html
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Forum whore
If there is any rule for the inexperienced to keep in mind. it is that everything a reasonable intelligent person should intuitively believe to be right will probably be totally wrong.
http://www.bmw-m.net/techdata/cylinder.htm
The inlet port needs only a slight convergence of 1.5 degrees included angle, which doesn't sound like much. But a 12 inch section of aluminum pipe taper-bored for a 1.5 inch inlet and a 1.498 inch outlet flows better than a parallel-wall pipe, and a lot better than air going from the cones' small end to it's beg end. Sound waves love a divergent duct, air flow does not.
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now where's some dirt!
In 01 RS125's converted to a head like that, supposedly it gives a better power delivery for running off unleaded. I think around 03-04 they went to flat top pistons for the a-kit ($10k+ engines) for again better power delivery for the unleaded fueled bikes. Afaik all the world gp bikes run flat top pistons and i would guess a combustion chamber of some shape like that. I was told it helps push the fuel mixture back down towards the piston before the spark plug fires.
For the leaded fuel everyone still runs dome top pistons and a standard shaped combustion chamber. Its a bit hard to know what to do though. Since world gp converted to unleaded in 97 (I think?) all the development has gone down that avenue. There are only a couple of countries that still allow leaded fuel so we just stick to the tried and true and that seems to do the trick
Fair weather rider
TZ as your looking at combustion chambers and transfer patterns I found this for you. It talks about the pistons head/squish area on the left being from the old school of 50% bore dia and the one from a head made with an eye on the MSV Mean Squish Velocity produced.
From:- http://www.saltmine.org.uk/shoeman/heads.htm
"Piston on the left came from a motor using a conventional head design. It has suffered some detonation as shown by the small pieces of carbon that have been knocked off the centre of the dome. Note how the baked on stuff extends all the way to the edge of the dome in parts. The piston on the right was used with a well developed squish design head. The area of maximum heat has been confined to the centre of the dome. No carbon and oil residue approaches the sides of the dome at all, indicating no mixture is being trapped there and burning on. You can also see evidence of the flow pattern in the cylinder by reading the shading on the dome. The cooling effect of the flow from the secondary transfer ports is very easy to see in the two very light coloured small areas at the top of the piston. This is what you like to see when you remove the heads from your motor."
More from the auther can be seen here:- http://www.saltmine.org.uk/shoeman/
Fair weather rider
Gold Mine:- http://www.2stroke-tuning.nl/media/i...dir=artikelen/
And :- http://www.2stroke-tuning.nl/media/index.php?
Mostly in Dutch but you get the idea.
Forum whore
This may be of interest "How to Choose a Power Band" by Eric Gorr.
http://www.whidbeyparts.com/info/How...apowerband.pdf
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Forum whore
MSV Mean Squish Velocity Calculator:- http://myweb.tiscali.co.uk/teamsparr...rheadsv2_3.xls
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Forum whore
Bugatti
The engine is about 12.66cc, one cylinder, 2 overhead cams and a supercharger.
http://www.bugattirevue.com/revue29/t72.htm
The smallest Bugatti, measures only 12.66 cc. recently photographed in France, the one prototype built in 1944. Dimensions are 24 x 28, plus supercharger and gear driven overhead valve gear. It was capable of 10,000 RPM. The detail pictures below speak for themselves, really a very fine piece of engineering!
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Forum whore
A page about moving heat:- http://www.koolance.com/technical/cooling101/002.html
After reading this I can see why TZ is using copper in his cooling system.
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