My wife and I love our 2003 Gary Fisher Tassajara's, and have so far only put about 15 hours on them. The LBS said when they get about 30 hours on them to bring them in for a tuneup. This weekend we took a 35 mile ride along the Schulkyill river trail near Philadelphia PA. (mostly pavement and/or gravel-packed dirt) and my wife complained several times that when going uphill or really cranking on the pedals, the bike was shifting on it's own without touching the shifters (Shimano Deore quick shifts) Before I take it back to the LBS, what should I adjust to prevent the unexpected shifts?? Is it the derailler or the actual quick shift that is probably causing the problem??? I'm pretty mechanically inclined (been away from bikes a number of years though) and was hoping you enthusiasts could help me out before I take it back to the LBS....Thanks