ive got a peugeot speedfight 2 50cc air cooled. and i have just bought 3.3 gram rollers and a high performance kevlar belt. is this what i want for better acceleration and top end? i also have got a speedfight 100cc. some people reccomend using the carb from the 100cc and put it onto the 50cc? what effect will this have? and is there anything else i can do to make it any better?

jamie, August 2010

i have got 5.1 gram rollers on order. and i've now decided that i'm going to get a 70 kit and a sprts exhaust. do you have any recomendations?

jamie, September 2010

i would try some 5 gram rollers and maybe a gear up kit on the standard cylinder sometimes a good 50cc motor can pull one but if its at all low on compression it wont,unfortunatley its never a case of how fast you can make it its how much your willing to spend on it !you could get it over 150mph if you spent enough on it mate of course it would be heavily modified with an entireley different engine and would cost a small fortune.

adam bike doctor, August 2010

hmm. so do you think that i should maybe go for 5 gram rollers? to even it out a bit? and maybe a better variator? the only thing is that i dont want to spend alot of money as im only keeping it for a year until i can get a car, then i will sell it, so is there anything i can do to improve it without spending lots of money on 70 kits?
thankyou.

jamie, August 2010

3.3 gram rollers are very light and while they may give a better pull off speed theres a good chance you will lose top end as they rollers are not likeley to be heavy enough to win the belt fight with the torque spring in the clutch,whcih basically means the rollers are not heavy enough to have enough force to pull the belt into the middle of the clutch even at high revs.putting a 100 carb may work try it but the main jet may be too big for a 50cc engine more room in the venturi means faster air flow but the fuel/air mixture must be relevant to the cc .to be honest you need to fit a good quality 70cc cylinder kit and a gear up kit if you want better top end speed.

adam bike doctor, August 2010