I have an 04 AC90 4 stroke. My son is starting to outgrow it. I don't want to buy a new machine just yet. What can I do to make this faster? I already took out the spacer on the clutch. Thanks

 

we have put on a few pipes and bigger carb on some machines and has improved alot over stock we gain about 6-10 mph and about 3 to 4 bike links out of the gate

 

Theres one in the carb also.

 

Replacing stock rear sprocket to a 35 tooth will give about 8mph top speed, airbox/exhaust mods and rejetting give much better acceleration. We use a tractor supply muffler thats only $25 and go up about 4 jet sizes on the main. Clutch mods like rollers,springs and drilling the rear clutch are cheap/free and help alot. I usually replace the front variator with a better one with correct ramp angles and lighter rollers. Many mini atv 2 stroke companys can help and sell rollers etc. Hetrick,WRH

 

By going to a 35 tooth rear sprocket, will I loose bottom end to gain 8mph top end?