TaoTao Thunder 49cc. Need advice on performance parts

[chaco]

Scrappydog scooters. They have plenty of parts. I would go with a bigger crab for one. A no rev cdi. And a clutch set up your bike will be running like 150. And of course an exhaust. They cdi will make a big difference with just that. But you change one part that you'll most likely need to adjust you air/feul ratio and jets.

[blueboy5000]

Mods will not make a 50cc a contender against even a stock 150cc. Mods to the 139(50cc), even BBKs, don't really give the 139 more top end. Fully modded, you'll be lucky to hit 50mph on flats.

A moderately modified 157(150cc) will hit 60mph, a highly modified 157 can hit upwards of 75 at very high rpms.

Sadly, no matter what you do to a 139, it'll never take a 157.

[blueboy5000]

Do the CVT mods first, then try it out. A bigger carb is unnecessary, usually you'll get what you're after with simple jet swap and carb tuning. A non BBK 139 engine is really small, so adding a bigger carb will result in poor performance.

I also point out, if speed is the concern, a 150 is the way to go.