Scootertronics offers NCY and OKO standard rollers weights from two high quality makers.
We offer both due to suppilers not always having one or the other in every size both NCY and OKO are same quality and you get same performance from either.
Get 5 or 5.5 with great take off for scooters getting upgrades to cylinders and exhaust
Get 6 to 6.5 for just switching out rollers and keeping performance you have when new and remember belts slip at 500 miles.
6.5-8 grams are stock in most chinese scooters.
The larger 7 and 7.5 are for very small people
A new set of 6gram rollers and a Golden Variator from NCY is a great upgrade plus add along a quality belt from Gates and you got a super upgrade for performance.