I have just bought a sprocket off of OldMiniBikes warehouse and installed it.The chain is now jumping the teeth.I have tried a new chain and a used one.It seems that the teeth are a little closer on the new sprocket than the old sprocket (I know its because the old one is worn out).I have alighned the clutch with the sprocket and tried many different things,but the chain will not just wrap around the new sprocket without a gentle nudge of my hand.Has anybody else had this problem???? The sprocket is not bent.Oh and it did try a new sprocket that does not go on this bike and it has no problems with jumping the teeth.
