ESE's works engine tuner

[Buckets4Me]

Do you think it necessary to have the plenum between the carb and the crank case ? Wouldn't a "pressurized" airbox be of benefit, without the risk of 1,5 liters of petrol vapor blowing your leg off..

Not being a naysayer mind you.. Just trying to work through the nuts and bolts of it.

the plenum has more air behind the carb ready for the engine to draw from instead of being choked by the carb. A pressurized air box would help but not as much. you could have both maby

as for it blowing your leg off, how big is the crank case volume and why dosent that blow up ?
why would a plenum be any more likely to go bang ?

[Henk]

I know there has been a fair bit of chat on here lately about forced induction two strokes of one sort or another but the rule book turns it into an interesting diversion and nothing else really.
To whit

All engines must be
normally aspirated except F4 4 stroke engines of less than 100cc capacity, which may
be turbo or supercharged.

[Buckets4Me]

I know there has been a fair bit of chat on here lately about forced induction two strokes of one sort or another but the rule book turns it into an interesting diversion and nothing else really.
To whit

All engines must be
normally aspirated except F4 4 stroke engines of less than 100cc capacity, which may
be turbo or supercharged.

Plenum is not forced induction

I think thow there is a 100cc 4stroke in the works with a turbo ( but that has to come after everything else. and there is a lot of everything else)

[Yow Ling]

Is that a Kawa 100 or 125 bottom end maybe???

Yea its one of those

[Henk]

Plenum is not forced induction

I think thow there is a 100cc 4stroke in the works with a turbo ( but that has to come after everything else. and there is a lot of everything else)

I know that a plenum is not forced induction but there has been plenty of spirited discusion here lately about turboed kreidlers and the like.

I'm not suprised you guys have plans for a blown 100 either, you seem to have either plans or work in progress on just about every possibility.

[Yow Ling]

I have had a bit of experience with blown motors over the past few weeks, blown FXR, G4 and blew my KC100. I think they are overrated , just seem to be constantly rebuilding them

[Henk]

I know it;s been said before but f*ck you guys are hard on gear down there.

[gatch]

as for it blowing your leg off, how big is the crank case volume and why dosent that blow up ?
why would a plenum be any more likely to go bang ?

Crankcase volume would be at a guess 1.5x (or there-abouts) the cylinder volume ? Plus with the restriction of the carb and whatever valving is sealing the crankcase, I imagine it would be a bad bad day if a crankcase ever popped.

Dunno, this is just me thinking about it, it just seems a bit dodgy having a big chamber full of vaporized fuel quite near to the exhaust. I mean obviously the concept works and it has potential..

Shh, just ignore me.

[TZ350]

........Dunno, this is just me thinking about it, it just seems a bit dodgy having a big chamber full of vaporized fuel...........

Yes at the first look its not a pretty thought, 1.5l of fuel/air mixture would be an explosive problem in a confined space and definitely dodgy but with the blow off valve and the carb there are plenty of places for the ignited gas to escape before it reaches an explosive pressure.

Having seen a few "Pops" I think the plenum is about as dangerous as a small backfire in a 4-strokes muffler, more fun than dangerous............

[TZ350]

........the plenum has more air behind the carb ready for the engine to draw from instead of being choked by the carb.............

Thank's Buckets4Me, that's it in a nut shell................ a real simple concept when you think about it.

[Yow Ling]

Another turbo 50 , might struggle round mt wellington but makes 20+ hp

http://buddfab.net/buddfabhomepage.html

[TZ350]

Yow Ling, thanks for the link you sent me, lots of interesting 50's on that one too. http://forums.autosport.com/index.ph...c=98711&st=200

[bucketracer]

A supercharged 1937 DKW and supercharged 1936 water cooled 500cc 2-stroke Scott from Britain.

[gatch]

A supercharged 1937 DKW and supercharged 1936 water cooled 500cc 2-stroke Scott from Britain.

That Scott looks pretty damn cool.

[Yow Ling]

Pretty interesting blog about some guy building his own moto 2 engine , untill they changed the proposed rules to one make engine. He decided to carry on and finish the project anyway

http://moto2-usa.blogspot.com/