How to Clean
A Bike Cassette
Having a clean drivetrain is essential to maintaining your bike's drivetrain performance and longevity. While cleaning and lubing the chain should be done on a weekly basis (if you ride multiple times a week), cleaning your cassette is important to do every couple of months or so when dirt and grease build up.
There are a couple different techniques that I use to clean cassettes. I'll call them the "quick" way and the "thorough" way.
Tools you’ll need for this job:
Cassette tool and chain whip (for "thorough" way)
Large crescent wrench
Quick cassette cleaning
The quick way is easy and only takes a few minutes to do. All you need is degreaser, a rag and a cassette brush.
Step 1: The best way to do it is to remove your rear wheel from the bike and set it on a work bench.
Step 2: Pour a little bit of degreaser into a small dish, or onto your brush directly.
Step 3: Use the brush to scrub the cassette, scrubbing the whole cassette and each individual cog. Try to get in between the gears as much as possible.
Step 4: Once you have scrubbed it down and loosened up the grease, grab your rag and use the edge to clean the excess out from in between each gear.
Your cassette should be decently clean and ready to install back on your bike. (Always clean and degrease your chain before doing this so that it doesn’t dirty up your cassette as soon as you reinstall it.)
Thorough cassette cleaning
The thorough way requires that you remove the cassette completely from your bike. To do this, you need the correct cassette tool for your bike cassette and a chain whip. The most common is the Shimano cassette tool which works for SRAM as well. If you are using Campagnolo, then you need a special Campy cassette tool.
Step 1: To remove the cassette, you have to first remove the wheel and quick release.
Step 2: Place the cassette tool into the splines of the cassette. Put the chain whip on the cassette so that the handle is on the left side of the cassette. The chain will wrap around the cassette and allow you to put a wrench on the cassette tool and untwist it.
Step 3: Thoroughly clean each cog with rags and degreaser. Some cassettes don’t allow you to remove each cog individually, but with it off the wheel, you can soak it in degreaser and scrub it a little better than when it is installed on the hub.
Note: When you are re-installing your cassette, make sure you don't forget any spacers in between the gears. The gears are designed to only fit onto the freehub in the correct position, so there is no way to install one backwards as if it were flipped over the wrong way. Also, be sure that you install each gear from the largest first, to the smallest. Once you have all the cogs back on the freehub body, tighten the cassette down with the cassette tool and wrench. You don’t want to over tighten the cassette lockring, but you don’t want to leave it loose either. Most models will start to feel like they are ratcheting when you tighten it down sufficiently.