Bicycle Mechanics - Do I need a new chain if I go from a 16t to an 18t cog (fixed)?

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Sincitycycler
02-26-07, 12:45 AM
I'm currently running a 48x16 and would like to go to a 48x18 - too many big inclines out here in CA!

Do I need to buy a longer chain?

jjvw
02-26-07, 06:15 AM
It depends on how far back your wheel is in the rear dropouts. If you can move it forward about half an inch you should be fine. I often switch between 46/16 and 46/18 on the same chain with no problem.
operator
02-26-07, 08:14 AM
You probably will just need to add a link or two if you want to keep your axle where it is in the dropouts currently.

urbanknight
02-26-07, 09:40 AM
If you're using a true fixie frame (long horizontal dropouts) you should be fine. I would warm up on my track bike with a 48/16 and race on a 48/14, and also experimented with chainrings from 46 to 50 without problems.
Sheldon Brown
02-26-07, 11:25 AM
I'm currently running a 48x16 and would like to go to a 48x18 - too many big inclines out here in CA!

Do I need to buy a longer chain?
Each tooth added will require the axle to move forward by 1/8". If you have room to move the axle forward 1/4" in the slot, you can use your present chain.

Sheldon "Doing The Math" Brown