i have a moded bws 100 = aerox 100 , stock cylinder bored to 58mm x 53mm crank = 140 cc , everything changed or moded , only case is stock , in summer lose all the power (aircooled = waste power & fuel), it vibrate , burn too much fuel , its junk
so get a 70cc minarelli or piaggio : fast , smooth , uses little fuel =less $