· Still needs a life.
Most of the recommendations regarding a 42T rear sprocket are for the ST4s, which comes with a 38T OEM rear sprocket. I don't know the size of the ST3 OEM sprocket or which size suits it best.oldguy said:I have seen a number of posts advocating going to a 42 tooth sprocket on the rear. If I do this, do I need to change the chain as well? Pros and cons of this mod? Any recommendations on the best source for a replacement sprocket?chain?
I have read that you should change both sprockets and the chain at the same time. If you are happy with the performance of your bike right now, I would wait until you need a new chain before experimenting with a new sprocket combination.