rear sprocket

[mike gp-1]

How small can you go on the rear sprocket with the stock chain before you have to remove a link or buy a new chain? the stock chain has only 400 miles on it and I really don't want to change the front spocket.

[Micah / AF1 Racing]

If your chain adjuster is all the way to the front side of the adjustment range then you should be able to go down at least three teeth to say a 44T rear sprocket. Changing the front sprocket is pretty easy once the bodywork is removed...do not be intimidated.

[RS50Jeff]

I have a 42 no problem. I don't know that anyone goes much smaller than that, because you can just get a bigger front to drop the ratio. I have gone 14F/42R with the stock chain.
Why do you not want to change the front? It is easier to swap, as you don't have to pull the rear axle out and take off bolts. It is just a snap ring. It is also about 1/3 of the price of a new rear sprocket. Sprocket Specialists will make any size you want.