Well Ive only had my mountain bike for 3 weeks and I bent the lowest gear outward so I cant shift into 1st or 2nd. Make sure you never buy a sunrace cassette! (I'm sure you all knew that). Anyway I think I'm going to get a XT cassette to replace it, unless someone has a better suggestion. I want to try and install it myself, will I need to get any special tools? Any tips you might have for me would be appreciated since this is going to be my first bike repair.