Hi, I recently bought a 2000 or 2001 Specialized Hard Rock MTB. When I bought it the guy told be to check and possibly change the chain since it skips a lot. I went to the local bicycle shop to tune it up and they called me back a couple of days later to tell me that it really needs a new chain and cassette. I make them to the necessary to get a good ride. Well, not I got it back and the bad news is it still skips. Not on all gears, but some do make the chain skip. I just had a couple of rides to date with it so can't tell exactly which gears cause a problem, will get you updated. For now, all gears in the back seem fine as long as I'm on the smallest one in the front. When I engage the second one in the front, it starts to skip. Now, I bought a cheap MTB last summer that had this same problem and it bothered me a lot, went for a free tune up once but the problem reappeared as soon as I removed the back wheel the change tire and put it back on. It is one of the reasons why I sold it, I couldn't stand this skipping chain. Should I run to the store to tell them something is still wrong or is there anything I should try before doing that? One thing is that I sold my car so now my bicycle is my only means of commuting. Also, any good books that would help with all those small problems especially for someone like me who plans to use only his bike for all his everyday needs? Thanks a lot in advance.