f4 rules and superchargers

[kave]

I was just reading through the rules for the F4 class, and noticed that you are allowed to have a supercharged 4-stroke as long as it is 100cc or less. Would there be any advantage to having a supercharged 4-stroke 100, as opposed to a non-turboed 150? Has anyone ever taken advantage of that rule?

http://www.hscsupercharger.com

[F5 Dave]

Only heard of 2 (ok 3), one used a victor engine as a compressor on a C90 engine. Apparently it went . . . about as well as a C90.

I'd forget about it. Size & weight the 150 is easy option, although 100cc 2 stroke has more potential, or at least has been shown to in practise.

Although Speedpro may pipe in, his take on it may be different, but until he finishes it its just talk
Probably more suited to a side car anyway.

[diesel pig]

I was just reading through the rules for the F4 class, and noticed that you are allowed to have a supercharged 4-stroke as long as it is 100cc or less. Would there be any advantage to having a supercharged 4-stroke 100, as opposed to a non-turboed 150? Has anyone ever taken advantage of that rule?

http://www.hscsupercharger.com

Give me six months and I will have a answer for you

P.S. Come on Newmanz! I PM my address last night lets get this shit sorted and that motor down here!

[gav]

Or you could finish the turbo CB100 you started?
PS. Tell James I have the MB50 electrics he was after, I'll have them at work if he wants to pick them up!

[speedpro]

F5 is right. The only reason to do it is because it's very cool. There's been a few as F5 says, quite some time ago. One was a VC160 lawnmower based compressor, another was a crankcase mounted homemade rotary-vane type and I seem to think there was a 3rd but can't remember it right at the moment(old age and bourbon). They both went well when they went but both had cushdrive issues which stopped them regularly. The sound had to be heard - a real bark with instant throttle response.

Once I get the FZR chassis sorted with both MB engines I'll drop in the FZR125(yes I know it's too big) and probably slap on the turbo, or if I can come up with a drive system that isn't too pricey I might go for the supercharger. I have a little rotary vane type but don't think it'll flow enough so would use the rootes type if i went that way.

[MVnut]

I must be drunker, thought u said F4s Rule ! )MV F4s of course )

[Kickaha]

The only reason to do it is because it's very cool.

Is any other reason needed?

Or you could finish the turbo CB100 you started?

To much like hard work, he came up with a much better idea

[F5 Dave]

Is any other reason needed?. . .

Potential fuel economy? He is getting older & these things start to appeal I'm told.

[FROSTY:Me]

Does a stroker have advantage down at your welly tracks?
At Mt wellington it seemed the out of corner punch of the 4 strokes was a winner.
Mind you so says a guy that raced a TF100 based bike--right untill I grabbed the wrong fuel can one day--Hmm Im told a 50-0 mix causes sudden detonation --eeep

[F5 Dave]

Hard to answer that, the 4 strokes have great pull out of the corners. However at kiatoke kart track the 3 front running bikes were all 2 strokes. To make it more embarrassing they were all 50s (we raced them all in as anyone who bitches about a bike half the cc is a bit sad). At the slipway only recently have I been occasionally beaten by a 4 stroke. But a 50cc is hardly able to grunt off the corners. Mine doubly so as it is heinously peaky. Mike Green on his fast MB100/RG could give me a pretty hard time.

I built a 125 2 stroke (air-cooled with 24mm carb restriction as per F4 rules) to try & make a bottom end grunt bike. Sadly this wasn't as successful as it could have been but a lot of it down to bike choice rather than the fact that is was 2 or 4 stroke. Although the bike did beat all the 4 stroke streetstock 250s & 150s at Taupo year before last, until it expired.

At mt wgtn the CB125 twins (150cc) built by John Connor are mega. But to clean them up you need a super hot 100cc 2 stroke as proven a few times by Nig Duff.