A stiff chain link can cause problems with your shifting, and can even cause injury if it slips while you’re pedaling. Here’s how to easily diagnose and fix the problem.

Find the Stiff Link

You’ll know you have a stiff link if your chain skips every 3 or 4 rotations. If you have several stiff links you’ll feel it skip even more often. To find the link, shift down to your smallest rear sprocket and then run the chain backwards through the derailleur by rotating your crank. Keep a close eye on your chain as it rolls over the lower derailleur pulley. When the stiff link passes through you’ll see it jump over the pulley. This means the inner and outer plates of one of your chain links are squished together too tight at the pin.

Loosen by Hand

To fix this by hand, simply work the plates loose by twisting the chain up and down the same way it was meant to. Then point the stiff link upward and firmly grab the closest connecting points on either side. Now twist the chain side to side, the way it was not supposed to bend. If all goes well, your stiff link should now be loosened and you can continue riding.

Loosen with a Chain Tool

If this method doesn’t work, and the link is still stiff, you’ll have to use a chain tool to fix it. Place the stiff link into the chain tool, on the slots closest to the turning handle. Now thread the chain tool’s pin gently against the chain pin about 1/8th of a turn, or just enough to slightly loosen the chain plates. That should loosen it enough.

If you still have problems, the chain may actually be bent and need replacing.

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