I got a pair of these for Christmas, but they don't seem to have any information on them as to the wattage they will draw from the system. Does anyone happen to know how much they will pull? I have 185 watts from the XR650L stator, but I am adding some ADVMonster 60 LED lights too.

i have a set on my f650gs and they work great! ran them last season and now this season with no problems so far. i dont think they take much wattage at all, i thought i read somewhere they take around 15 and 25 watts on high? the resistor gets way hot so make sure its not touching anything that can melt. i actually took the resistor off and run them straight on high.

If you've got an electrical meter handy that you can measure Ohms with it's a snap to do the math for Watts. Measure the resistance (Ohms) of your new grip heaters across the leads that would attach to the battery. Check both Hi and Low settings if you want both wattages. The math is Voltage squared, divided by Resistance (Ohms) equals Watts. So just round off your voltage to 13 volts (a few tenths either way won't be that big of a deal) then square it (13x13=169) now divide that (169) by the Ohms reading on your grips and there ya have it. mike

JMHO: Ditch the switch and resistor and spend $4 on one of these. Since it's PWM a lower setting draws less power. http://www.advrider.com/forums/showthread.php?t=737165

am i ok by just running them through the hi lo switch that came with them? i cut the resistor out and run them straight through the high setting on the toggle. they get pretty hot but feel great in the cold weather. does the hi lo switch have a resistor in it or is it just a two way toggle?

Easy - just measure the resistance of both together in parallel. Assuming it's "R" Ohms, plugging them into 12V will produce I = 12 / R amps. The consumed power then will be equial to 12 * I = 12 * ( 12 / R ) = 144 / R Watts