Sources I've read, and my own experience, indicate it's not necessary to discharge NiMH batteries before recharging. They seem to be perfectly happy getting "topped off" or recharging from fairly deep discharge (but NOT all the way, which can ruin them), unlike their detestable NiCD cousins.
Originally posted by Richard D
I seem to recall you also use the big Cateye BS rear lamp - how long do a set of NimH's last (do you run it on constant)?
I use a smart charger so, I can discharge them fully before recharging.