top speed question

[houg]

i have a 2002 cobra racer it has a 70cc big bore kit, 94 main jet, tecnigas pipe derestricted cdi and variator , it has the stock air box with restrictor removed, the spark plug is a greyish all most tanish color at full throttle the engine buries the tac needle it pulls me uphill no problem at all ( i weigh 237lbs )   but my top speed gps is only 45mph   my question is with this set up shouldnt i be hitting at least 50mph??  im not sure if my rollers are stock or not, i tried the dr pulley flat rollers 6.5 gram and then the 9.5 gram either did any good so i put the stock ones back in

[Snorvey]

If it buries the revcounter needle then it sounds like it's undergeared. On motorcycles*, that translates to more teeth on the front sprocket and/or less teeth on the rear. At the end of the day though, it's all about experimenting and compromising. Upping the gearing might mean a higher top speed, but you'll likely find it slower to accelerate and less happy climbing hills.

*I don't know how this translates to scooter rollers and weights and stuff. Sorry.

[houg]

well it climbs hills like a pissed off badger so i guess if i gain top speed like u say then ill loose it on the bottom end witch i dont want too

[GLV55]

well it climbs hills like a pissed off badger...

Ha Ha Ha! I love that description - I'm going to use it, often! Thanks for the laugh. 

[MJR]

well it climbs hills like a pissed off badger

That reminds me.

[Mr. Paul]

Badgers? We dont need no stinking Badgers!! 

[Redk]

The Cobra of the Sierra Madre, no doubt.
redk

[randyo]

If it buries the revcounter needle then it sounds like it's undergeared. On motorcycles*, that translates to more teeth on the front sprocket and/or less teeth on the rear. At the end of the day though, it's all about experimenting and compromising. Upping the gearing might mean a higher top speed, but you'll likely find it slower to accelerate and less happy climbing hills.

*I don't know how this translates to scooter rollers and weights and stuff. Sorry.

my experience with motorcycles is that gearing doesn't have as much to do with top speed as horsepower,  for instance, my SV650 could go faster in 5th gear than it could in 6th.  RPM in 6th gear was not cranking enuf horsepower to overcome aerodynamics. I could actually go 3-4mph in the lower gear, not sure if this comes into play so much with a scooter,