Re: Sprocket question.
Make a mark aligned with one tooth on the sprocket then rotate your rear wheel, counting the teeth until you came back to the mark you made.
As was said by matthurd, the standard kit supplied sprockets are usually somewhere in the 44 to 48T. Remember; the smaller the sprocket, the higher the gear. Too small and your acceleration will suffer, the larger the sprocket, the lower the gear. Too big and your top end will speed will go down. The 40/41T is a good all round gear for most riders.
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