DH took my 20 month old bike in for a tune-up. The mechanic told DH it needed a new chain (ok...) and a new sprocket ( ). My husband gave him the go ahead for the work. Got the bike back today, and the biggest sprocket in the new cassette is only 23 teeth. The old one had 25. I really need at least 25 to climb hills around here.

I will take the bike back and ask them to switch out the cassette. But just curious: how many teeth on your big sprocket? And isn't it strange that a cassette needs replacing after 20 months? Old one was a Shimano, new one is SREM, if that makes a difference.

Thanks for your input.