Can this be fixed?

[Wrench]

Looks like the motor mount did that damage

 

[Andrew1234]

looks like an aluminum crack to me. not worth it toss the bike. find a steel frame and get rid of the ragjoint sprocket

I got it from a trade I never use rag joints ever so not my fault

 

[Andrew1234]

How did that happen? Do you attribute it to the motor alone, vibration?

I have no idea I got it from a trade

 

[Jayraye39]

I got it from a trade I never use rag joints ever so not my fault

Not holding u liable. It takes a while to learn these things but in this forum you have members like the ones in this thread that will help guide and jumpstart your learning. we are always just giving you good advice. just letting you know the rag joint will destroy every rim you put it on and they are dangerous. the hub adapters for holding the rear sprocket are also garbage your gonna want rims that have brake rotor holes. there are 6 of these small holes on the hub of the rims (drive side) that a sprocket will bolt right up to. This is the safest and most reliable way to fix the sprocket to the rim.

 

[Jayraye39]

The 40t sprocket you have now will not work. but you can get a sprocket with the 6 holes for like $13 on ebay or amazon. 36t is the best tooth for top speed and torque without sacrificing one more than the other.

 

[ImpulseRocket]

The 40t sprocket you have now will not work. but you can get a sprocket with the 6 holes for like $13 on ebay or amazon. 36t is the best tooth for top speed and torque without sacrificing one more than the other.

I've got a 38T on my bike with a 203mm rear disc, and someone else here managed to get a 40 to work as well. If the dropouts can manage to move the rotor out enough and the caliper and mounting bracket have some adjustment range to them both vertical and horizontal, it is possible to fit a larger than 36 tooth. Just takes the right combination of bike and parts.

If the bike has a caliper mount between the 2 dropout tubes, the chain is not present to cause clearance issues with the caliper and allows for pretty much any size rear sprocket.

 

[CrazyDan]

It would be much cheaper to replace than fix.

 

[Jayraye39]

I've got a 38T on my bike with a 203mm rear disc, and someone else here managed to get a 40 to work as well. If the dropouts can manage to move the rotor out enough and the caliper and mounting bracket have some adjustment range to them both vertical and horizontal, it is possible to fit a larger than 36 tooth. Just takes the right combination of bike and parts.

If the bike has a caliper mount between the 2 dropout tubes, the chain is not present to cause clearance issues with the caliper and allows for pretty much any size rear sprocket.

no im saying his current ragjoint sprocket wont work because it does not have the 6 small holes. then just gave advice on a better tooth for performance on the stock 66cc 38mm CG