Originally Posted by Ekdog
How often do you find you have to change them?
When I was still using wireless, keeping the bike out one night in -10 to -20C pretty much killed the batteries. Bringing them inside for a while before next ride revived them somewhat, but after a couple of nights nothing really helped. Wired LCD screen goes blank too after some time in such temperatures, but it logs the information nevertheless. Wireless was utterly and completely dead.
The storage room I have for bikes is a bit warmer, say above 0C at all times, so that was way better. But there's no way to stop the batteries being exposed to cold when riding, so it became too much of a hassle in any case.
I only had the wireless setup for one summer, and during that time I never had to change batteries. Problems started with winter.
--J