Originally Posted by
bobn
I would like to change out the 18 tooth to a 22 tooth sprocket on my 3 speed. There isn't enough room left on the drop outs so the chain will have to be lengthened. Anyone have any idea how many links I would need? Can I add extra links using connector links?
For each tooth added/subtracted to a sprocket, the axle must move 1/8" (3 mm.)
For each complete link (1 inner + 1 outer) the axle moves 1/2" (13 mm).
However, different makes/models of chain sometimes have different thickness pins. As a result, you may not be able to find a matching link.
Chains are cheap, my advice is to replace the present chain along with the sprocket.
Sheldon "Chains" Brown