Bicycle Mechanics - STI shifting woes in cold weather

Since the roads have been clear lately, I've been taking out the "good" road bike that has STI levers instead of the old beater with downtube levers. But I'm having a lot of problems getting it to shift in the cold (~20F). The bike has full Ultegra 8-speed circa 1997 (but the bike was bought new in 1999).

The problem is that the little insert levers don't engage and I can't shift to a smaller cog or back to the small ring. After repeated attempts, the levers sometimes finally shift. I have also found that slight forward pressure as I push the lever in increases the chance it will engage.

The shifting worked fine when the weather was warm and it works fine on the indoor trainer. Any ideas?

It sounds like the grease is gummed up. I don't know how your mechanical skill are, but if it were me I would take them apart and clean them.

If you have never had them apart then no is not the time to learn (unless you are comfortable buying new levers after you fail to reassemble them). Sounds to me like the grease gets cold and stiff which is common in shifters to some extent. Go to your bike shop, get a can of Clean Streak made by White Lightning and use it to "hose" out your shifters. Pull the brake lever so you can access the internals and then spray it in where the shifter cable head is and operate the shifting. You should notice a change in how positive the indexing is almost immediately. Hope that this helps, if you want to use some spray teflon plus or another thin oil to relubricate the internals of the shifters in the same manner as you cleaned them.

-Ryan

Along with the levers your brake cables may be slowing down as the lubricant has 'stiffened' up. Time to clean and re-lube. To see how well your lube flows when its cold put it in the fridge. I have some Mobil 1 lube that flows great when its cold.