Joined: Aug 2010
Posts: 472
Likes: 0
From: Washington
Bikes: Serotta Davis Phinney, 1992 Serotta T Max,1984 Specialized Allez, Olmo, 1974 Strawberry,Redline bmx, ect.,
The shifters are probably gummed up from lack of use. There is a hole inside of the shifter buttons were the cable goes in, squirt some lube like Tri flow or WD-40 into the hole and then shift it through the gears till it frees back up. This should fix it but on a rare occasion the shifters might need replacing,New 21 speed Shimano shifters are around $35 and labor .