Just picked up this 07 YZ450F today to use as a Timbersled host for snow riding. It is in OK shape apart from the dirty air filter (ack!) And the cold motor puff of smoke on throttle whacks that goes with the dirty air filter. I got the price down low enough ($1350) to make it worth a buy.. So I'm going to take the head off and inspect and most likely do the valves etc.. Should I go with stainless valves and kibblewhite springs? It will be run very very hard in the snow.. Not uncommon to be pinned for minutes at a time. Anything else I should do to increase durability while I have the head off? I'm also planning to run heated grips and maybe a small light. It looks like Rickystator just started selling a 35w stator for this gen YZF. Is the stocker good enough to power heated grips? 35w is pathetic.