Yes Husa, it seems to be as you say it is.
Yes Husa, it seems to be as you say it is.
Niels, maybe another risk of unit crankcase chamber, could be detonation in overcharged one cylinder, at certain different condition.
For NS 500 3V engine, because of the higher temperature, center lower cylinder compression was reduced in comparison to vertical side cylinders.
Just remember 1991 Hans Becker modified TZ 250 DP4 engine with Hans Hummel big bore cylinders. Huge over-square 67,5 mm bore and std 50,7 mm stroke. 363 cc -91,2 hp at 10668 rpm, 20 hp over std 250 cc
Later 54.5 mm stroke crank was used with slightly smaller pistons, 375 cc.
Big surprise that this kit still available
http://www.geckomotorcycles.co.uk/ma...-bore-kit.html
oddly i cant remember posting this stuff at all wtf
https://www.kiwibiker.co.nz/forums/s...post1131038334
Here is a Konig cranks
as well as the modern better made ones
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Kinky is using a feather. Perverted is using the whole chicken
It has been argued that having a two cylinder boxer two stroke will beunstable in amount of air fuel mixture distribution from an undivided crankchamber.
The Koenig won a lot of races ,was basiclly two independent air/fuel wise boxers with two cylinders each served from an undivided crank case.
Is that fact or fiction?
A picture of the rotary valve face will b very nice if someone has one.Please?
I got a monster McCullough 4 cylinder two stroke drone engine from our Navy once and I seem to remember that it was two crankchambers feed from reed valves from one common carb?
Well it wasn't so informative.
Another unit crank chamber type, copy of Konig, that was made in small series. Both with the same 54 mm stroke, but 45,3 mm bore for 348 cc. Runs on Methanol
Veterok-70 348 cc 70 hp at 9000 rpm
Veterok-100 496 cc 100 hp at 9000 rpm
i cant recall who did this one.
Frits will though. it was out of some sidecar
okay
https://www.flickr.com/photos/teamhe...57594456814612here are some pictures of the Stredor, a work of art made by Egbert STREuer and Rinus DORgelo. This machine was on display at the Speedshow in Cafe Hofsteenge in Grolloo
plus some others one reed aparently based on the yz250
no idea of the internal layout
The other I would like to replicate (as for no other reason it looks frigging cool)
I can't remember what it was called but i think it was three leter E..
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Kinky is using a feather. Perverted is using the whole chicken
Boxers can have common or sealed individual crankcase chambers.
For direct exhaust they can be common
http://miniairboatassoc.com/forum/sh...1-Drone-Engine
The disappointment Andreas swedish friend had (letter 36519)was most likely trying undivided crankchambers with modern resonnance exhausts.
Modern military drone two stroke boxers do not have tuned exhausts .
This is the only other picture that I have of this engine.
Add other outboard racing engine picture from sixties. This is the development of soviet 1962 single-cylinder racing engine "Hurricane-175", developed on the basis of the Zimmermann disc intake engine design, a sample of which was handed over to soviet racers by its designer Daniel Zimmerman.
175 cc 60,5 x 60,5 mm bore/stroke
27 hp on pump fuel
Carb 30mm
Ex 189
Intake 198 opened 52 after BDC
Trans two mains-132 C-129
Exhaust stainless 0,5 mm
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