hi harley i read the spec on your scoot, they must be the slowest 150cc ped in the world but most of the chinese bikes are designed for fuel economy rather than speed. without ever working on your type of bike i'd expect it is restricted probably in the same places as most peds, variator, exhaust, carb & possibly cdi. your supplier should be able to tell you where the restrictions are & if you're ok with the spanners then its a cheap fix. im not to sure its a good idea having your scoot doing 90mph, the build quality wouldn't be as good as the jap stuff but i hope this helps........happy motoring.
steo
June 2009