I was wondering if anyone has ever had this very strange problem with their shift kit that I just can't figure out for the life of me. So my problem is adjusting the two mount plates on either side of the engine that hold the shaft itself with the bearings. First, to clarify, I have a 10 tooth output sprocket on the engine, a 17 tooth sprocket that receives the chain from that engine output sprocket, and another 10 tooth jackshaft sprocket on the right side of the bike. When I say left or right side of the bike I mean from the viewpoint of the sitting on the bike. this is the kind of shift kit that I got:
https://www.bikeberry.com/motorized-bike-jackshaft-kit.html
When I have them (the two mounting plates) lined up to make the shaft exactly perpendicular to the bike the 17 tooth sprocket on the left side of the bike has no problems because it is perfectly parallel with the output 10 tooth sprocket from the engine. However! the 10 tooth jackshaft sprocket on the right of the bike will not properly receive the chain from the lower crank sprocket at the pedals. The chain is slightly wider than the sprocket teeth and tries to walk off the sprocket to the outside of the bike. I finally figured out why it was trying to walk off and it is because the right sprocket it somehow at an angle to the chain and not receiving it straight on but at an angle. When I adjust the two plates that support the jackshaft to change the angle of the jackshaft and thus the sprockets to allow the right sprocket to receive the chain properly then the left 17 tooth sprocket doesn't revive the chain from the engine output sprocket properly and will often break the chain. I have never found a perfect angle for the jackfast because even if I make a compromise angle on either side then both sprockets have issues. I'm 99% certain that my engine is mounted parallel to the bike and thus parallel to the pedal sprocket. Recently I got the angle of the jackshaft to a point where the chains on either side stays on the respective sprockets but the 10 tooth right side jackshaft sprocket is wearing into the inner side of the chain and is thinning out the chain plates.
When the jackshaft is adjusted to be perpendicular to the bike (like it should be) and there are no issues with the left sprocket there doesn't seem to be any angle on the right sprocket but it has the problem described above. It doesn't look angled with respect to the chain but it still has the "walking off" problem that is only solved by changing the sprocket's angle. I just don't understand why there is this problem and how to solve it. The only solution that I can think of is to remount the engine at an angle on the bike but I'm not sure if that won't cause other problems.
https://www.bikeberry.com/motorized-bike-jackshaft-kit.html
When I have them (the two mounting plates) lined up to make the shaft exactly perpendicular to the bike the 17 tooth sprocket on the left side of the bike has no problems because it is perfectly parallel with the output 10 tooth sprocket from the engine. However! the 10 tooth jackshaft sprocket on the right of the bike will not properly receive the chain from the lower crank sprocket at the pedals. The chain is slightly wider than the sprocket teeth and tries to walk off the sprocket to the outside of the bike. I finally figured out why it was trying to walk off and it is because the right sprocket it somehow at an angle to the chain and not receiving it straight on but at an angle. When I adjust the two plates that support the jackshaft to change the angle of the jackshaft and thus the sprockets to allow the right sprocket to receive the chain properly then the left 17 tooth sprocket doesn't revive the chain from the engine output sprocket properly and will often break the chain. I have never found a perfect angle for the jackfast because even if I make a compromise angle on either side then both sprockets have issues. I'm 99% certain that my engine is mounted parallel to the bike and thus parallel to the pedal sprocket. Recently I got the angle of the jackshaft to a point where the chains on either side stays on the respective sprockets but the 10 tooth right side jackshaft sprocket is wearing into the inner side of the chain and is thinning out the chain plates.
When the jackshaft is adjusted to be perpendicular to the bike (like it should be) and there are no issues with the left sprocket there doesn't seem to be any angle on the right sprocket but it has the problem described above. It doesn't look angled with respect to the chain but it still has the "walking off" problem that is only solved by changing the sprocket's angle. I just don't understand why there is this problem and how to solve it. The only solution that I can think of is to remount the engine at an angle on the bike but I'm not sure if that won't cause other problems.
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