I have an 11-25T cassette with a Sora derailleur on my road bike. There are a ton of hills around me that I am struggling on when I'm on my road bike but not my mountain. I can easily remove the cassette, and I am wondering: Would upgrading to a 11-34 or 11-32 cassette be a simple swap? Would I need a new chain with more links/less links removed to accommodate the 11-32/34 cassette?)
It would be neat to have my fast setup and a climbing setup with a chain to match each cassette, though it would be simpler to use the same chain for both. Let me know if you have any experience doing a swap like this. Any information is well appreciated.