Chain will not stay on

Jessica:

First, check the chain and sprockets. Check the two chain sprockets for worn or bent teeth. If either of the sprockets is damaged, replace them. If the sprockets are OK, Check the chain for any damage If the chain is damaged, replace it. You are checking the chain for kinks, stiff links, damage to the link side connectors, and checking that the chain is not bent (side to side) Check to see If the chain is loose. If it is, you'll need to loosen the rear axle nuts and pull the rear tire backwards to tighten the chain, then tighten the rear axle nuts. *Make sure that the rear sprocket lines up with the front sprocket*. Just lay a straight edge along the two sprockets, ( A yardstick will do), and make sure that the sprockets touch the yardstick along the whole length of the sprockets. If the rear sprocket is cocked (not lined up with the front sprocket) loosen the axle nuts again and push on one side of the rear tire or the other side until the sprockets line up.
When you are finished tightening the rear axle nuts, pull up on the chain between the sprockets... the chain should not move up or down more than 1/8 of an inch. The chain will stretch over time, and you need to check the chain for looseness before riding.


Happy and safe riding!