px gearing

I need some help on this as its got me a bit p$%^& off,the scoot will pull like a CR250 in 1,2,3 and in 4th but when i give it some stick it runs out of steam at about 80-84mph…this speed was verified by the police at the time at a cost to myself so i know my speedo is not correct as it gave me a reading of 75mph…The gearing is 21/68…anyone know of a better setup as it will pull a bit more but the ratio is pullin it back.i did a plug chop and it was as normal as its ever been…

tuned malossi 166 barrel
reprofiled head
cut crank
30 dellorto
cases welded and tuned
lightened flywheel
carbon fibre clutch (sparkright technologies)
reprofiled intake


sorry vespamalossi, I didn’t understand your problem. If your kit runs out of steam at around 80mph with a gearing of 21/68 you should be satisfied. You could try the 21/65.

[:D] Good one mate…i was wondering what the screaming was…i wish she would find a different way of seeking my attention[:drink:]

You could use a 100/90x10 tyre? its slightly wider but a lower profile, and is smaller than 3.50x10 so should lower the gearing.
cheaper and quicker! plus you can flog it if it don’t work!!

Do you not find that pair of feet slowing you down?

Hi Curare…i should be satisfied with it but you know yourself how it is, if its asking for more why not try to give it some more…i will give your ratio a go and see if it makes a difference…cheers mate…[:dance1:]