I'm not 100% sure about tooth count on each cog, but I think it's something like:
23, 21, 19,17,15, 14, 13,12 (probably?)
I'm having issues with the size of the cogs. Climbing even basic hills is very hard even on the biggest cog. (It's wearing out my knees).
Can I change the cassette to one with bigger cogs without replacing my rear derailleur? Or would I have to get a new derailleur also?
While at it, can I get smaller front chain rings without replacing the front derailleur? I have 53T/42T chain rings.