In response to JGoody--I had a set of these
on my SV650 and they worked really well. Solid state controller that's smart enough to turn off when it senses battery only voltage (bike not running) so you don't have to find an ignition circuit. (I would anyway, though) You might have trouble finding a spot for said controller, the F800 doesn't seem to have as many nooks for that sort of thing. ALOT warmer than the factory grips so pretty much guaranteed you can't just splice it in to the factory wiring. I've thought pretty seriously about ditching the factory grips myself, they're not as warm as my R1150R grips much less the 3rd party grips.