I have a Sirrus Elite disc with an 11T-30T cassette 9-sprocket that needs to be 34T or 36T low end in order for me to climb Seattle's hills at an 80+ RPM. I'm thinking of switching the rear derailleur to a Shimano SLX and finding a cassette 9-sprocket that will work with my OEM Sora 9-speed shifters. I would need a longer chain too for the larger gear. Is their a 9-speed sprocket available that goes from 11-36T or 34T?

Lars

Shimano and Sram cassettes will offer the lower gear and because you are buying a new cassette,
it would be foolish to not start out with a new chain, as well..

11-34 Sram : https://www.amazon.com/Sram-CS1-PG970.../dp/B003WOIOHM

Thanks! Just wondering about performance difference between 30T and 34T. Will it be enough?

Lars

I only looked up the 2013 Sirrus Elite with Disc model, you have the same front chain ring as my FX 50/34. I stay on the 50 in the front most of the time, but live in flat Florida. If I was back in North Carolina, 34 front by 34 rear would be fine, after that I would be pushing anyway.

I was just at a bike event last night with a bike shop vendor there with a mechanic. He said I wouldn't need a bigger rear derailleur than my OEM one to handle going from a 11T-30T to a 11T- 34T rear cogset. He said he only would have to add a few links to the chain for the bigger cogset too. The other bike mechanic said I would need a larger MTB derailleur. Can anybody tell me who is right?

Lars