Fewer gears more beers.
Sometimes you need a smaller cog, sometimes a bigger one; luckily, the Surly Single Cog caters to your fancy. The machined SCM415 Cro-Moly steel cog features a tall tooth profile to prevent chain skip and work with 6-9-speed 3/32in chains.
- Available in every increment from 13-22T for perfect gearing\
- Stackable and derailleur compatible for a multi-speed drivetrain
- 8- or 9-speed chain recommended but will work with 6- and 9-speed 3/32in chains
- Heat-treated for ultimate strength
- Chrome-plated for surface hardening and improved chain lubricity
- Fits Shimano-compatible freehub bodies
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Reviews & Community
20t just installed, time to spin it up!
I'll have another!
- Familiarity: I've put it through the wringer
I guess you can say Surly is starting to grow on me... This is my 3rd Surly cog within the last couple years. I've got a 16t and an 18t and I love them to death, except when it comes to some of the more hill filled courses. I needed something not so tall, so I snagged the 20t this time around. Five minutes later, I am rollin' a tad easier on up the hills. I'd like to say the 20t helps out just a wee bit more, but on a SSCX bike, it's all pure pain; we'lll see how this season goes.
These things can really take some abuse. Like mud and snow crunchy munchy abuse. My cross bike is steel, so I figured I'd stick with the theme and keep the cogs steel as well. I've had friends run some aluminum cogs and after just one season, their stuff is usually mangled and toothless.
PS. These things are nicely priced!
- Familiarity: I've put it through the wringer
This is one of the best SS cassette cogs on the market. It's tough and nicely machined. Weight is reasonable (though if you're that concerned then you're being silly). It's steel (as any SS cog should be) and wears almost negligibly.
What makes this better than most is the wide base (4mm) that does not chew up cassette freehub bodies, not even lightweight alu or Ti ones. If you have XTR hubs with the Ti freehub body, this is a must. There are others (Niner, CK) that have this as well, but they're much more expensive.
On top of all of that, it looks good. The larger cogs have nicely spaced drilled holes that probably shave negligible weight but just look cool. The blasted finish is nice and even and well done.
The weights (measured) of the cogs I have:
I put the 22t on my new single speed because the one I had was kicking my ass and it's a great improvement for my weakness. It's a solid gear for climbing and keeping a good pace on level ground, not to mention it's a burly little guy.
Out lasts everything.
I love this cog and I have tried everything out. Some have work well for a while and some will bend or snap after a week. This Surly Single Cog is how all bike components should be made, to with stand the test of time. They have a wider base that keeps your freehub body in perfect shape. You can also find a perfect chain line with out moving to much. Just flip it over for 4mm inside or outside, spacer kits sometime don't have one small enough for that fine tune adjustment. These cogs have a tall tooth profile that is essential for preventing chain skip from the extra torque from a single speed drivetrain. Another thing I love about the cog base width is 4.35mm, so I stack a 4 of them up and use a 9-speed shifter for a slop style/ free ride set up. And I have never had my chain fall off and I mean never. Spend a little more now and save a ton in the long ride.
Why are these cogs meant to fit 8 or 9...
Why are these cogs meant to fit 8 or 9 speed chains, aren't these cogs usually used for SS? Will they work with a single speed chain?
1/2x1/8" chains vs. 1/2x3/32" chains. 1/2x1/8" chains suck. Run whatever you want, but bigger isn't better here. Yeah, they're wider, but according to manufacturer-supplied data, they're not stronger and they are definitely not of better quality. Multi-speed drivetrains is where the bucks are at, and chains that work on such drivetrains are where the manufacturers of chains showcase their innovations and developments in quality. The rollers are better, the plates are better, the pins are stronger, and the construction method (riveting procedure) is better on all multi-speed 3/32" chains. I guess if you grind your chainring and chain down the handrail every night at the local pub, a bigger 1/2x1/8 " chain will last longer, but most of us don't and it won't. If you have an old Singleator: Dammit, don't use a 1/2x1/8" chain!!! Otherwise, you'll tear the Singleator off the bike, among other things, guaranteed. This is no longer the case with our redesigned Singleator. The old version used a loop over the jockey wheel to help keep the chain in place. This loop would catch 1/8" chains, which are fatter than 3/32". The current Singleator uses guide plates on each side of the jockey wheel to achieve the same purpose, but depending on the orientation of the wheels, it can run 3/32" or 1/8" chains. We still prefer narrow chains, but if you absolutely must use an 1/8", the new design will work for you.
Very tough and won't destroy alloy freehubs.
Been riding with these Surly cogs for over 3 years. I have three of them ~ 16 tooth, 18, and 20. I swap them out before a ride depending on the terrain I'll be on. The wider base of the gear does exactly what it's claimed to do. There are no signs of wear or damage on my freehub, and the cogs themselves still look as good as when I first bought them.
To be honest, I never noticed if they were heavy or not. After all, it is only one cog compared to an entire cassette. Only a weight weenie would take issue with these cogs. Everyone else will be pleased with the long life and no damage to the splines on their freehubs.
I'm not necessarily a weight weenie but even I couldn't but this thing on my bike. Felt like a brick compared to my CK 20t. I know the CK is a little smaller. Went with the Niner 22t instead.