I am thinking about putting heated grips and a heated seat pad on my 03' trx250 sportrax. How much wattage does it take to run the bike itself? I know the charging system is 123 watts, and the headlight is 45 watt. How much of this is extra wattage?

 

not much- I don't know the exact #'s but those systems put just enough out to run your lights at night... you'll probably be okay with grips, but the seat might be too much- especially if you're riding at night.

I ride when it gets down in the teens- the only thing that freezes on me is my fingers and nose- the seat gets warm after a few minutes of sitting on it and I also have 3 layers of gear on.

 

yeah, get you some carhartt bibs