Scooterotica

well here is the latest update on this,...and i,m still not happy with it cos although ive stripped it ,and rebuilt it with porting its still not perfect yet I,m afraid. So i,m gonna strip it again ..
the good news is that its now getting approx 23/24 bhp after porting the cases to match the barrel,I also modified the piston holes /cut outs to give more area and flow as recomended by malossi/sip ...
I didnt touch the crankshaft in this case but did give it 360 degrees intake by cutting a tunnel port from the intake to the barrel ..over and above the crankshaft ...as can be seen on previous reed valve tunes that i have done and as shown on the "scooterotica"tuning pages ..
3 or 4 bhp increase in power may not sound like a lot for the time and effort required ,but in % terms its equates to approx a 20% gain over a 20 bhp motor which aint too bad me thinks ... :lol
and the reason why i,m stripping it yet again ? ..well ,although ive cured the kick start lever stripping prob ..its still not returning up properly ..and also the freaking bronze clutch bush decided to weld itself to the clutch pressure pad (which i have never seen before lol)..oh and one more thing ..the rear hub still feels loose on the axle splines ...so much so that even after replacing the rear axle bearing ...its never gonna pass an mot
,so going to have to put in another shaft ...what an arse hey

interesting thread... specially as..... from page 1......



"I am not sure if you guys know that much about 2-stroke tuning. It seems to me more theoretic knowledge than verified."

re - the clutch pressure plate problem. SIP used to do an all in one pressure plate and plunger with a bearing inbetween . dont know if you can still get them, but worth a try.

sean brady scooters wrote: the good news is that its now getting approx 23/24 bhp

Sean.
Is that with the Malossi exhaust? Did you manage to coax any more torque out of it?

SF

yes its still the malossi pipe,and i,ll post up the dyno results when we finally test it again as its all ready again now ..I think (fingers crossed)

well we have just dyno,d it again tonight ,and feel now that its performing as well as can be expected ...
power /bhp was up as I said ,but torque only ever so slightly up on the peak .
but the spread of usable torque was increased ,by an extra 2 ft/lbs , as was seen not only before peak power but also after peak revs so i guess thats an improvement overall and should make it more usable and rideable ..

sean brady scooters wrote:well we have just dyno,d it again tonight ,and feel now that its performing as well as can be expected ...
power /bhp was up as I said ,but torque only ever so slightly up on the peak .
but the spread of usable torque was increased ,by an extra 2 ft/lbs , as was seen not only before peak power but also after peak revs so i guess thats an improvement overall and should make it more usable and rideable ..

ok so how much has this engine cost in man hours and stuff to get to where you are now?

Christ only know's but I assume the motor is the same as a Cambodian whore who doesn't f@@k yet provides a "happy ending".

I.E. - a pile of wank

Juan wrote:Christ only know's but I assume the motor is the same as a Cambodian whore who doesn't f@@k yet provides a "happy ending".

I.E. - a pile of wank

Harsh. I suspect the pipe is holding it back.

SF

i take it from the lack of response thats its been flogging a dead horse and you wish you never started it then!