How do I tighten a bike chain?

The chain of a single-speed or hub-geared bike or e-bike needs to be tightened periodically due to chain stretching. Typically, this is done by loosening the nuts of the hub and moving the hub backward in the dropouts. The chain tension is correct when you can lift the chain about 10 mm. A chain that is too tight will cause unnecessary wear on the bearings.

When tightening the nuts after moving the hub, chain tension is easier to control if you first tighten the nut on the chainring side. After this, while centering the rear wheel in the fork, you should tighten the nut on the brake arm side.

Sometimes moving the hub also requires loosening the brake arm attachment. If this is necessary, it is especially important to secure the brake arm firmly after tightening the chain. If the attachment is left loose, the brake arm may come off while riding, which can cause the hub to break and damage the frame.

If you are uncertain about performing this procedure, or if you are unable to do it, we recommend contacting a bike service shop. You can conveniently find our dealers here.