Originally Posted by
gecho
Lithium in general doesn't do very well in the cold, which is why I picked a light with huge rated runtime. This week I got less than 2 hours from my XML-3 on low which is rated at 10 hours.
At least the lights with a separate battery pack you can keep the battery warm. I used to put my Stella battery in a small camera case.
My knog blinders don't put out much light, but I've had them work reliably down to -30C. If I were to guess, I'd say that the Cateye has a contact somewhere that contracts just a little too much, leaving the light without a complete circuit. A 2 hour run time should still be better than 10 minutes, even in the worst cold.