Latest Discussions : Miscellaneous


05:53PM | 04/27/05
Member Since: 04/26/05
1 lifetime posts
i recently purchaced a "mini chopper"motor cycle and the problem i have is the fact that the bike has no"low" end torque. do to the fact that it has a centrifical clutch drive system.after you get hte bike moving it has alot of "top end speed" in fact i have gotten the bike to 65mph but like i said the problem is in the low end torque or lack there any way i could modify the clutch or motor to gain the low end torque the bike and i crave? by the way the motor is a 49cc engine. and help in this mater would be great. my e-mail address is


04:18PM | 04/28/05
Member Since: 11/13/04
90 lifetime posts
depending on parts availability, you may be able to tune the clutch more to the motor. it may need heavier springs or wieghts to utilize the torque of the motor, not sure how the clutch is set up, but usually it consists of some sort of wieght/spring arrangement, a heavier wieght/spring will cause the clutch to engauge later in the rpm range of the motor, moving the clutch engaugement higher into the torque curve of the motor, giving a better low end response.

a gear change may also give the desired result.


09:10PM | 05/09/05
Member Since: 05/08/05
3 lifetime posts
Your problem is more likely the gearing rather than the clutch. The clutch should be fully engaged shortly after you increase the engine speed and after that it is simply locked up. Unless it is slipping, which it doesn't sound like.

The fact that you can go 65mph indicates the gearing is too high. Most likely you will need to change the relationship of the front gear to the rear gear, they are the sprockets on a motorcylce though. What you need to do is increase the size of the sprocket on the engine, or decrease the size of the sprocket on the rear wheel. You will sacrafice top speed but gain low end torque.


09:13PM | 05/09/05
Member Since: 05/08/05
3 lifetime posts
I got it backwards, you should DECREASE the front sprocket or INCREASE the rear sprocket... Or you can do both.

Its been a while.....

Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.

Reply choose button


Post new button or Login button