Just replaced the stock 11gm rollers on my TGB101R 150cc for a set of Dr Pulley 10.5gm sliders. An amazing difference to both acceleration AND top speed. In fact, mid-range acceleration has been given a sizable boost too. When you've only got 10bhp to play with you need all the help you can get. I'm getting sets of 8g and 9.5g also to see just how fast off the mark the even lighter weights can make the little buzzer. I ride 50k every day through Melbourne peak hour arterial traffic so I'd happily trade off a bit of the 100 kph top speed for a faster blast off the line. It might gain even more top speed if this info below from a Dr Pulley specialist in the USA applies even at low slider weights. cheers Mark For your info if you are interested : Sliding Roller Weight ( US7276004 ) vs. Round Roller People know that the round roller weight is not always "rolling" in the ramp (the runway for the roller ); actually the movement of RR (round roller weight) is a hybrid movement "rolling & sliding". The features of Slider (sliding roller weight, or SR) are: 1. The shape of Slider is designed to i. make its initial low position lower than that with stock round roller. So the low gear becomes much lower and therefore able to get a higher acceleration; ii. form the flat front side of Slider, which enables the Slider move more outward than round roller does. Therefore, V-belt moves much higher; i.e., the high gear becomes much higher to get higher top end. iii. Thus, the take-off rpm with Slider is about 300~500 rpm higher than that with round roller, and the top end rpm is 300~500 rpm lower than that with round roller. Consequently the Slider can make the range of gear shift become broader. 2. Through the physics view, the work needed to move the Slider (from bottom to top position) is 2 x F (force) x S (distance of ramp) while the work needed to move the RR is 2 x F (force) x S + 1/2 x M V2, This shows the movement of Slider is faster than RR. 3. The Slider is molded from material SL-9T (self-lubricated polyamide 46 ), which has low friction of coefficient, high wear resistance, high heat resistance and contains no abrasive filler (do not wear aluminum-made variator). So, the durability of Slider is excellent.4. The stability of gear shift ratio of SR is much better than the Round Roller that means the fade of CVT performance is much less for SR.