Drive chain is not feeding onto the front sprocket. (please help!)

[Filip]

So, I was intalling my 80cc kit on my bike and I noticed that when I engage the clutch and the rear wheel was suposed to spin freely it didn't. It has this weird jerky motion and gets occasionally stuck or locks up, then it spins freely for half a turn and locks up again. While examining the potential cause of the issue I noticed that the chain is not properly feeding onto the small front sprocket. The highlighted part of the chain has lifted up onto the sprocket. Any help on how to fix this problem would be greatly appriciated.

 

[Steve Best]

Sprocket problem. Probably too wide in spots, maybe it has burrs?

 

[crassius]

sprocket probably has flat topped teeth and chain has the heavy and wide rollers that are getting stuck on them - one can make the chain really tight and roll it around some till it stretches a bit or better, just file the teeth a bit more pointy on top

 

[Wags]

I have had the same problem. There are two different front sprocket widths. One can take standard bike chains like the 410 and the other is made for heavy duty 415h. All you have to do is either get the smaller front gear. Sick bike parts has the smaller width sprocket or file the sides and tips of the sprocket until your chain fits. You could also get the larger 415h chain, if you don't already. Do you know what size chain came with your kit?

 

[gasbiketommy]

In my opinion, if your chain tension was too loose, with all the flapping around, it probable rode up on the sprocket and damaged it. Everything must be tight and secure, I hope this helped. Good luck buddy, don't get too stressed, these things happen.

 

[gasbiketommy]

In my opinion, if your chain tension was too loose, with all the flapping around, it probable rode up on the sprocket and damaged it. Everything must be tight and secure, I hope this helped. Good luck buddy, don't get too stressed, these things happen.

The only other thing I can think of is if you used an after market chain that doesn't fit properly.

 

[bakaneko]

i concur with crassius. the teeth on the drive sprocket brand new is no where near what the teeth on a drive sprocket should be. they are usually more squared at top and larger than needed.

you can either file them down or the easier route is to tighten up your drive chain to no slack (very tight) and make sure the alignment is near perfect and then just pedal it around for a mile or two trying to start it. the chain will bundle as you mentioned but just back up the bike to loosen it and then keep going forward. eventually, the sprocket teeth will wear down (it is actually faster than you imagine) to the point where it will no longer get stuck like that.

 

[Gasbikejerry1967]

In my opinion, if your chain tension was too loose, with all the flapping around, it probable rode up on the sprocket and damaged it. Everything must be tight and secure, I hope this helped. Good luck buddy, don't get too stressed, these things happen.

 

[Gasbikejerry1967]

Arrow racing sells a guide that is supposed to eliminate chain lock up you will have to drill into your sprocket cover cost is around $40. I've had similar issues and a minor increase in chain tension helped if ur running stock tensioner you might try a spring tensionet.I did and my chain headaches went away for the most part.hope this gets you out in the wind ride on brother