Yamaha Vino 5 AU slightly larger than the genuine pulley diameter and 1 g heavier weight roller increased the maximum speed by 5 to 10 km / h. On the other hand, of course, the acceleration gets dull, but it is somewhat level. People who want to swing in the acceleration direction will need to lighten the weight rollers. Moreover, there is a part which is concerned about the molding state of the resin part of the weight roller (it is somewhat how to cut off the runner) and it was shaped and then assembled. I think that COSPA is good as a whole good. It is recommended.
I bought it for the refresh of the drive system of the live Dio ZX (AF - 35). Installation was not too difficult as long as even tools are available. The only regret is that the light of the hole in the lamp plate on the back of the pulley was somewhat small and could not be installed, we replaced it with the thing that was originally attached (normal item) and managed it. Please be careful when you use it for live Dio ZX (AF - 35) and purchase it.
Certainly the fastest speed has gotten faster by nearly 10 kilometers, but I think it would be better to attach it with a bore-up kit, although a flat road is good but the car speed does not grow if it is a little climb uphill.