[inuyasha]

Hi
You want heavier roller weights not lighter, those 4 gram weights will most likely raise your rpms even higher
http://www.monsterscooterparts.com/r...ght-guide.html
I would get a roller tuning kit and experiment until you find the proper weight for your riding needs
http://www.scooterworks.com/prima-ro...p#.Ud758DvrwSk
Once you find the weight then get a set of quality rollers or sliders as the tuning ones are not for every day use, Dr pulleys or ncy are my recommendations
if you decide on sliders( which are my preference) go up 1 gram over the roller weight, so if 6 gram rollers are perfect go with 7 gram sliders
Hope this helps
Take care and ride safely
Yours Hank