in relation to chris stack's query, i too am having similar probs 8000 on the clock!!! however, i do know that to improve scooter performance you can get new exhaust or different tyres, using superplus petrol won't make an inch of difference.
you can also change the rollers on your variator, but i don't now too much about this... in other words get an haynes manual!!!
marlene
December 2009