not that i know a darned thing, but i prefer to ride (at least a couple miles) on any work i do before a race. how many times have you had to stop on a ride and make another subtle adjustment after working on your bike?
don't let it wait until the last minute, unless you're a factory mechanic and make no mistakes. if all is well, the night before a race i pack my bike in the truck, and double check all my gear, and relax.
-mark
www.motosapiens.net
(off-road adventure for the sentient being)