I have an old 1973 Ted Williams Free Sprit(Yes I know, its a bottom line but restoring and riding older ten speeds is my thing) that I restored last summer. Well the weather here in southern MO hit a high of 50 so I had to get out. Well I started to go up a hill and the shifting handle was very hard to push down. it went all the way down but the damn thing didn't shift. The chain just stays in the smallest cog. There is no tension screw either so that's not the problem. The derailleur barely moves but not enough to shift and I even adjusted the cable.