Hi Just purchased a 1992 Peugeot Festina Chromoly Frame Road bike. The previous owner had possibly used it in a single gear because the bike will not change gears. It has the Shimano RSX shifters & dérailleur. I am not sure how to adjust the gears, when moving the shifters, nothing happens, but i can manually with my hand drop the chain down the cassete. I think it maybe something to do with the 2 screws on the rear deraillier and the gear cable tension screw, but i am not sure if i would also need to make any adjustments on the shifters. I am presuming there must be a mothod of adjusting the gears so that they do not change, I need to reverse this so i can use the gears, as the bike is a beauty and rides really nicely.