Changing a fixed gear cog

craker

Any tips on replacing a fixed gear cog (on a 2015 Langster)?

After barely 5000 miles the teeth are looking quite shark-finned. I would let it go but there's an annoying creak coming from my transmission somewhere (bb - check, wheel bearings - check seat post - check).

Looks like you can pay anywhere from £5 to 30 for a single cog, I'm tempted to go cheap (those who know me would not be surprised :shock: ). Any good justification for a more expensive one, have you got a recommendation? (Usage is year round commuting).

I can't think what the lock ring looks like on the Langster. I may have a tool that came with my Lidl toolkit all those years ago, it's certainly got a chain whip.

Any truth in the assertion that the lock ring has a left hand thread (anticlockwise to tighten) and the cog a right hand thread? That just can't work unless there are two different threads on the hub.
http://thebiketube.com/tutorials/diy-remove-fixed-gear-cog-home-without-special-tools

paulwood

By the time mine need replacing they are on so tight that removal without the tool would never happen. Pretty tight even with the tool.

I tend to buy cheap and treat them as consumables.

imposter2.0

Not sure if you were being ironic when you say 'barely 5000 miles'...

Miche, Halo, and plenty of others all make decent track cogs. Not a great deal of difference really, but if you are expecting one to last longer then 5000 miles, then don't.

You'll need a c-spanner for the lock ring (LH thread) and a chain whip for the cog itself (RH thread). And yes, there are usually two different threads on the hub. No idea what's on yours though.

Matthewfalle

I paid a fiver for a 16 tooth Shimano one from Evans. Can't go wrong with that.