Help! Need Chain help!
- Thread starter WATONGA
- Start date
Help i have a 48cc Chinese engine on a normal street bike and my chain keeps kicking off my sprocket! My lines are correct, strait line between engine and sprocket. Help!
Check the master link.
Make sure tension is correct 1/2" to 3/4" free play at the loosest point.
Triple check the alignment.
Make sure tension is correct 1/2" to 3/4" free play at the loosest point.
Triple check the alignment.
Also make sure the sprocket is aligned parallel to the plane of the wheel. Just check the distance from the sprocket to the spokes at several points and make sure they're the same.
You don't mention if you are using a tensioner.....
If you want help! put up a few large clear pics of your setup
Side view and looking from the back of the bike
what is a "normal" street bike?
pics would help....is it goin inward or outward?
i had a chain problem, the chain kept goint inward....i noticed how it went out thru the lower part, while the upper part of the chain seemed alligned
i had a chain problem, the chain kept goint inward....i noticed how it went out thru the lower part, while the upper part of the chain seemed alligned
I would recomend the modification of a rear derailer for a tensioner, all the cheap tensioners out there are dang near worthless, whereas the derailer is already perfectly designed and street tested for durability. With the ones I customize I flip it over backwards, drill out the little screw holes and mount the derailer gear to the lowest part of the arm, make sure of your spacing and use washers to space it apart. Do not use the secondary plate just drill out the one for the bottom gear and run a strong bolt.
Alot of the rear sprockets when new are a little too thick. Try wrapping the chain all the way around the rear sprocket and see if it kinda rides up on the teeth instead of seated all the way down. If it does just dress the teeth with a flat file till it fits like it should.
if the chain was lined up straight it wouldnt pop off. mine is off by 1/8" and so i use the tensioner to align the chain with the rear sprocket and it works great.
if your chain keeps kicking off sounds like you didn't de bur sprocket - this is old post - so i hope you it figured out by now 
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put the stock tensioner on,use a bolt behind it and 2 hose clamps on the bolt: this will keep the tensioner from going into the wheel.
adjust tensioner,but not too tight,walk bike and watch chain,listen for clicking and see how chain comes off,adjust chain tensioner in or out to line of chain with rear sprocket.
walk bike again to test it out. check motor mounts ,maybe engine is moving causing chain to come off,dont over tighten mount bolts or they will break,just snug will do and double nuts.
also is your wheel bent or not on straight,check that too.
adjust tensioner,but not too tight,walk bike and watch chain,listen for clicking and see how chain comes off,adjust chain tensioner in or out to line of chain with rear sprocket.
walk bike again to test it out. check motor mounts ,maybe engine is moving causing chain to come off,dont over tighten mount bolts or they will break,just snug will do and double nuts.
also is your wheel bent or not on straight,check that too.
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