Replacing a Bicycles Rear Sprocket Cassette

A rear bicycle cassette allows you to change from a big sprocket to a small one, enabling you to either go faster or climb hills. You can also replace your cassette for one with bigger sprockets which is better for hill climbing. Replacing the rear sprocket (cassette) on an electric bike does not need to be done by a bike shop. With a couple of special tools, you can do it yourself. This instructable shows you how.

If you don't already have a 'bike tools kit', a sprocket remover and chain whip can be purchased for a modest price.

Rear wheel cassette

Sprocket Remover/Chain Whip

1. Remove the rear wheel from the bike.

Using a 'chain whip' and the special socket, remove the nut holding the cassette. This may be on quite tight and may require taping the tool's handle to make it move.

1. Notice the groves on the shaft - the new cassette fits onto these grooves.

1. Install a new cassette by aligning the groves and sliding on.

1. Tighten the nut back on. This can be done by holding the wheel and tighten with the special socket. The chain whip isn't required to retighten the nut.

1. Reattach the wheel onto the bike. Taking note of how it fits onto the chain and chain tensioner. (Top tip, do this before removing the wheel).
2. You are on your way again.