Originally Posted by
martslc
Thinking about swapping out my 10 speed Shimano 105 cassette, 12/25 to a 11-34. Front is a compact 50/34.
Can I just purchase the long cage for my current derailleur? I'm wondering if I need anything else other then the long cage and a new chain??
Thanks,
Marty
If you don't cross chain you won't even need the longer chain and I'd try using what you have right now before getting a new derailleur. Cage length is more to do with derailleur capacity and longer cages really only are needed on triple setups. As long as you don't cross chain you won't need a new chain either. 50x28 uses more chain than 34x34 will.
Concerning the derailleur, I have two bikes with 11-32 cassettes with a quoted max cog size of 28. One of them didn't even need any b-screw adjustment right out of the box (maybe 1/4 of the way screwed in). The other needed pretty much max b-tension. Anyway, you should try what you have before buying a new derailleur.