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SurlySingle Speed Cassette Cog
4.8
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Surly's cassette-type cogs are designed to fit on standard Shimano compatible freehub bodies. These cogs have a tall tooth profile that is essential for preventing chain skip from the extra torque a singlespeed drivetrain encounters. In addition to being a stellar SS cog, the cog base width (where it contacts the freehub body) is 4.35mm, so you can stack a few of them up and use a 9-speed shifter for a simplified multi-speed drivetrain. This width also prevents it from ruining the freehub body as a result of digging grooves into it like skinny stamped cogs have a tendency to do. Surly cogs are machined from SCM415 CroMoly steel, then heat-treated for toughness and chrome-plated for surface hardening and enhanced chain lubricity. These cogs will work with 6-9-speed 3/32" chains, although we recommend the inherently updated quality of an 8 or 9 speed chain. They are also available in every increment from 13-22t, so you can select that perfect gear.
Silver - 13t UPC
708752032071
Silver - 13t MPN
FW2071
Silver - 14t UPC
708752032088
Silver - 14t MPN
FW2072
Silver - 15t UPC
708752032095
Silver - 15t MPN
SURLY-COGHG-15T-3/32
Silver - 16t UPC
708752032101
Silver - 16t MPN
SURLY-COGHG-16T-3/32
Silver - 17t UPC
708752032118
Silver - 17t MPN
SURLY-COGHG-17T-3/32
Silver - 18t UPC
708752032125
Silver - 18t MPN
SURLY-COGHG-18T-3/32
Silver - 19t UPC
708752032132
Silver - 19t MPN
SURLY-COGHG-19T-3/32
Silver - 20t UPC
708752032149
Silver - 20t MPN
SURLY-COGHG-20T-3/32
Silver - 21t UPC
708752032156
Silver - 21t MPN
SURLY-COGHG-21T-3/32
Silver - 22t UPC
708752032163
Silver - 22t MPN
SURLY-COGHG-22T-3/32
Tree Fort ID:
333222338203
Review Summary
LIKES
Installation (7),
Simplicity (9),
High Quality (9),
Wide Range (1),
Value (6)
WORKS FOR
Mountain Biking (11),
Conversions (6),
Road (4)
DISLIKES
none
4.8 GEARS
16 reviews
16 reviews
Customer Questions
Q.
asked by: a guest
I have a 2020 Kona Unit, it has a freehub. Will these cogs work?
I have a 2020 Kona Unit, it has a freehub. Will these cogs work?
A.
anwered by: canteau
The Surly cogs are designed to fit a standard Shimano HG style freehub body, you will also need a spacer kit if the bike is currently set up as a multi-speed.
The Surly cogs are designed to fit a standard Shimano HG style freehub body, you will also need a spacer kit if the bike is currently set up as a multi-speed.
Q.
asked by: djj...@....com
Can these be used with a Nexus 3 IGH?
Can these be used with a Nexus 3 IGH?
A.
anwered by: canteau
The Surly Cog will not work on Shimano 3-tab hubs.
The Surly Cog will not work on Shimano 3-tab hubs.
Q.
asked by: a guest
weight
weight
A.
anwered by: canteau
The 16t Surly Single Speed Cog has an average weight of 62g
The 16t Surly Single Speed Cog has an average weight of 62g
Q.
asked by: a guest
What tool do I need to install and do I need spacers/lockring for my Surly single spd hub?
What tool do I need to install and do I need spacers/lockring for my Surly single spd hub?
A.
anwered by: mlewis
If your hub is a threaded hub, this cog will not work. This is designed to be used with Shimano type freehub bodies. Give us a call directly if you need more help!
If your hub is a threaded hub, this cog will not work. This is designed to be used with Shimano type freehub bodies. Give us a call directly if you need more help!
Q.
asked by: a guest
Is the width of this cog compatible with a Nuvinci IGH? Do I need any spacers?
Is the width of this cog compatible with a Nuvinci IGH? Do I need any spacers?
Q.
asked by: a guest
What is the diameter of the 17t cog?
What is the diameter of the 17t cog?
A.
anwered by: mlewis
I measured a 17t cog at exactly 3" in diameter.
I measured a 17t cog at exactly 3" in diameter.
Q.
asked by: a guest
Will these cogs damage an aluminum freehub body?
Will these cogs damage an aluminum freehub body?
Q.
asked by: a guest
Do you sell the lock nut to attach this to my hope pro hub?
Do you sell the lock nut to attach this to my hope pro hub?
Q.
asked by: a guest
Will these cogs bolt to a disc brake mount?
Will these cogs bolt to a disc brake mount?
Customer Reviews
5
April 11, 2011
reviewed by: taylorburch
Very nice, very solid cog. Well made and has extra width at the base so it doesn't eat away at your freehub shell.
vote
vote4
June 30, 2010
reviewed by: danthesoundman
Thick, hardcore and strong. Nice quality.
5
March 12, 2011
reviewed by: johnknopf
I'll echo what others have said. This is a good sturdy cog, but it does have spacing built in to one side, so if you want to flip it around you'll have to change your wheel spacers. (But then I'm not that cheap and would probably rather put in a new cog than flip it around--which I'm not sure would even work based on the Shimano cassette format.)
I'm running a 14 tooth on a fixed 29er built for road commuting. No complaints.
4
October 27, 2010
reviewed by: nic...@ya...o.com
This cog is heavy, but so is everything surly makes. Its great if you dont want to spend the money on a stainless cog. the only thing i dont like about it, is that you cant just flip it around when its worn without adjusting your chainline a little.
5
November 03, 2012
reviewed by: dfinocchio
These are the best on the market. They last forever (I have over 2000 training/racing miles on my 17t and it will be good for another 2000). They are much quieter than the cheap stamped-style, and the wider profile on the spline really does save your rear hub. I will never buy anything else!
5
October 20, 2014
reviewed by: popevil
Dropped from an 18t to 17t on my Kona UNIT SS to make it more cruiser friendly when I ride with my bride. Made a big difference, but I might get a 16t eventually. Also, I didn't have a spanner wrench, so I used a brass drift to turn the nut and it worked great, although the bike is fairly new.
5
January 20, 2011
reviewed by: TravisFulton
The Surly cogs and the spacer set make it easy to adjust and get the chainline dead straight.
5
August 18, 2012
reviewed by: A Guest
Surley's single speed parts have consistently impressed me with their build quality. These cogs are tough and resilient. They ride smooth also. Ive got mine on a converted Giant I've done with a singleator. Works great as a city bike and a mountain bike. I ride in western north carolina, and the bike is rigid so it takes a pretty good beating.
5
November 20, 2012
reviewed by: jhh...@ho...l.com
Great strong cog. They're thick and won't tear into your freehub body like many other cogs. I run Surly cogs on all of my single-speed bikes. I've never had to replace one either. A very inexpensive upgrade to any SS.
5
March 12, 2013
reviewed by: jeepskate
Simple part, does a great job. Wide base prevents hub damage and cog is offset for even more chain line adjustability.
4
September 09, 2010
reviewed by: qaidj
Nice, simple, clean piece. Fits nicely on my Shimano (former 7 speed) cassette.
Not many do, but I wish I could get this rear cog in a color other than silver and with 12t.
5
February 22, 2017
reviewed by: 1man1bike1gear
Stout cog. Runs smooth. Not sure about the holes; thinking they might make it a tad awkward to clean. Seems strange that Surly would employ such weight saving measures.
5
January 27, 2021
reviewed by: anonymous
Very high grade single speed cog that takes a lot of abuse and won't destroy your free hub. It's very wide at the hub interface so as not to gouge it, which is much better than several other much thinner cogs I have seen. It is quite a bit heavier than those aforementioned cogs though.
5
January 31, 2011
reviewed by: joh...@gm...l.com
beautiful construction and nice design. very happy with this item.
5
May 03, 2017
reviewed by: 1et...@gm...l.com
Solid component. You can buy fancier, lighter or more expensive cogs but these are strong and dependable. I've used them on a couple of my bikes without any issues... ever.
IMHO, Surly cogs are worth every penny and represent a good value.
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