Thanks for the input Lukas.
I went looking for the write ups you mentioned, but couldn't find them. I tried searching for MOSFET and also by user name... Any links to those write ups? I'd like to read them.
The grips I put on were the KTM hard parts version with 4 settings (though they're all pretty hot). I had to trim the throttle grip a bit, and when I did I noticed that I could see a fine metallic mesh between the layers of rubber. I'm hoping they're efficient.
Also, using a DC capable inductive amp meter I measured:
With the clamp around the positive wire at the battery, at idle, no accessories running, current flowing through is hovering around 1 amp (12w).
With heated gear going full blast, it's around 8 amps (96w). Put the high beam on and it goes up to 13 or so (156w). Anything off idle and these numbers go up.
So if we're talking 12V, the 224w charging system puts out 18+ amps.
When I look at charging voltage, with grips and all gear on the charging voltage at the battery does not go much higher than 12.8 at idle, and into the 13's at 4000 RPM. With less gear on, that number rises. I did sap the battery a bit when I was trying to see what just the gear and headlight draw with the bike not running. With everything on full hot and even the high beam on, but engine off, it spiked a draw of about 16 amps off the battery. So if the engine running at idle with no gear on is 1 amp, and everything else is 16, then I have an amp left, or 12w of charging, at idle. Makes me miss my BMWs...
I think to be safe and know I'm always going to have a charged battery, I should not use everything at once like I did during the test. I don't think I'd want everything on at full hot anyway... it'd be too hot. I probably won't be riding too often at night in the cold with the high beam on either. And I think the heated gloves draw less than the heated grips, probably have to run them at less power to get the same effect.
I just don't want to cook any important charging system components. So, if I could learn more about that MOSFET upgrade, that'd be helpful.