I just started riding my 2006 Hardrock after allowing it to sit in the garage for a few years. I really only rode the bike as a commuter and started riding off-road a few weeks ago. I replaced the chain and rear cassette because of wear (chain slipping). Everything was fine for the first 4-5 rides. During the past 2 rides, however, I have a very loud creaking when the in the small, front chainring, when there is a load on the chain. The creak does not occur in the middle or large ring. Any ideas?