Shifter problems when cold

There is a spring loaded item that is probably not catching. Have you opened up the shifter and tried to simulate it? Drop some degreaser in there and relube it. Throw it in the freezer to bring it to problem temp.

page54 said:

😕 [font=Century Gothic] I have a Cannondale T700 touring bike with RSX Shifters. They are about 5 years old and when the temperature gets near freezing and below the small lever on the year ago and has gotten worse.[/font]
[font=Century Gothic] RP[/font]

jasong said:

There is a spring loaded item that is probably not catching. Have you opened up the shifter and tried to simulate it? Drop some degreaser in there and relube it. Throw it in the freezer to bring it to problem temp.

The small lever RELEASES a ratchet(nothing catches), and spring tension in the derailers does the rest. Stiff lube either in the shifter mechanism or derailer casing is the likely issue.

Yeah, exaxctly what I've seen on another guy's bike.

boudreaux said:

The small lever RELEASES a ratchet(nothing catches), and spring tension in the derailers does the rest. Stiff lube either in the shifter mechanism or derailer casing is the likely issue.

The metal parts in the shifter contract slighly when it is cold and the worn shifter will have even more slop than it did before. Also the sifining of the lube can play a factor but I am guessing your shifter is just about dead.

As Boud said, I would first suspect and do a quick check on the rear derailleur. When it seems to be sticking I'd drop the rear wheel (preferably with no cable tension on the RD if you can get shifted to the small cog) and see if it returns smoothly and with some force with the spring to the outboard (small cog position) when pushed to the inside by hand.