Caporegime
If you're just talking spare parts then a SRAM cassette is perfectly good.
What about the chain ring,I see my bike has 3x chain rings near the pedals,Might as well replace those if im going to the trouble of replacing the cassette,chain etc..then its all new.
Or at least replace the one the chains on the most,which is the middle one..infact i never use that gear so its always stuck on the middle ring,The only gears i change are the one on the cassette.
Yeah that looks a bit too complicated for me lol,Maybe not the cassette part but the chain and everything...nah,Best i take it to a shop,At least then if anything goes dodgy i can just take it back and get them to sort it.
Meant to ask in my lat reply,What can i do about my knees!
My knees have started hurting lately and i think its because of the bike,I have the saddle up high (as im quite tall) high enough so when the pedals low my legs fully stretched but no matter how i adjust my saddle hight i still get dodgy knees.