GY6/QMJ157 Dr. Pulley Sliders
If you are looking to improve the performance of your GY6 150cc engine, this is a super easy solution. Lighter sliders raise the overall engine rpm. Dr. Pulley sliders are much better than rollers. Simply put: you will get a lot more action out of your variator resulting in more power. We've found that 11G is great for if you are under 200lbs 10.5 if you are over 200lbs. Otherwise grab a varitor tuning kit for fine tuning and grab the weight that works best for you.