I have trek 1000 and am upgrading my gears from 6 to 9 speed. I believe i have to buy/do
1) new 9 spped cassete which is compatible with wheel (shamano hg50 11-25)
2) new chain (new thin one)
3) new chainset **need advice**
4) adjust gears **looking forward to leaning how to do this properly**

My problem i have is that i don't know what chainset i require as don't what my bottom bracket is! Can anybody give advise and how easy is this to do? Thanks Newbie