Park Tool GSC-4 Cassette Cleaning Brush

I have used Park Tools' GSC-1 Gearclean brush for years, and it does a good job on chains, chainrings and cassettes. The GSC-4 is more specific to the cassette - it's wider, and the bristles are angled and contoured for that single purpose, so it's more efficient for that purpose.

I did have to figure out the best way to use it. The angle makes it "one-way" (hold in your right hand while standing behind the wheel). If the wheel is off the bike, it will only work on the push. On the pull, the cassette will simply spin. And I do prefer to use it with the wheel off, since otherwise the chain is in the way. Bottom line - if your cassette is dirty, this brush together with the right cleaner/degreaser will quickly get it clean.

This makes cleaning a grimy, dirty cassette much easier. It is shaped nicely to rotate the cassette on the wheel while keeping the brush still, or doing it the other way around. Whatever your preference this brush does a great job cleaning it up!

Park Tool quality. Stiff but flexible enough for the deep clean and so far hasn't frayed out like the thinner more common cassette cleaning brushes. My cassettes and chainrings have never been shinier! Who new a brush could bring so much happiness.

A quick easy way to get the dust off your cassette, a couple of minutes of brushing will rid your dust. I also use it to quickly brush off my derailleur wheels and chain when I don�t have time to throughly clean my drive chain.

Absolutely perfect for getting all the grime out of your cassette and derailleur rollers! Spray with your soap and water solution or bike cleaning product of choice and spin the pedals. The angle on the brush works it's magic and really cleans well. The bristles are stiff an durable. I use a bio based cleaner with this brush that's a little more than just soap but it cleans very well and then easily rinses out. I wish I had this product a while a long time ago. This is FAR better than a tooth brush or other softer brush you might have laying around.

I've got the other Park Tool for cassette cleaning (narrow brush on one end, plastic teeth on the other) and I'd compare two by saying this brush is the toothbrush and the other is the floss. This brush is great for getting a lot of gunk/dirt off the cassette quickly. I've been waxing my chain so I don't get a lot of oily build up on the cassette any longer, but I can accumulate a lot of dust/mud gravel riding. This brush quickly removes a lot of that gunk where it matters, i.e., where the cassette actually touches the chain. The deeper area between the cogs can wait for when I'm doing a major mid-season cleaning.

After the first use and storage the bristles were not straight. Maybe my fault for how it was packed with my other cycling tools. It performed okay, but its unidirectional for a right handed person. I typically use the edge of a rag to clean in-between my cogs if I am not removing them for a complete thorough cleaning. The brush helps remove the larger contaminants but I still had to use the rag after.

Well-made brush. I expect it to be durable. Functional design.

Pretty straight forward. A brush to clean your rear cogs. Simple, affordable and effective.

Brush is dished for better contact on the cassette and other parts.

This the best brush to clean the cassettes and get that grime and dirt off. I use it on my wheels as well and it works perfect.

The bristles are contoured to follow the shape of the cassette and allows for cleaning while it is still on the wheel. Easy to use.

Very well designed brush - typical of Park Tools!

Great for any bike but mtb's in particular.

Use for cleaning cassette, works Great with MucOff. Just spray and brush off - clean as a whistle. No more using toothbrush.