I'll copy paste some posts I made years ago. TLDR .. I rode my NT all winter with heated: jacket liner, pants liner, glove liner and boot inserts. I never killed the battery .
Now the wall of text...
I ran full heated gear on my previous Honda and never drained the battery, its alternator only had maybe 50 watts more available than the NT does.
It's kind of annoying, but it involves some basic math and common sense usage of the gear.
The NT's alternator produces 438 Watts at 5K RPM. This is at or below highway cruising speed where you'd feel the need to turn up the heated gear, so I feel safe using that as the number for the total available power.
An * denotes estimated, everything else is values straight from the NT manual.
55w low beam
55w high beam
21/5w Brake - Tail Light (x2)
21w turn signal front (x2)
21w turn signal rear (x2)
5w position light (you could pull this and save 5w)
5w plate light
60w fuel pump*
50w ignition*
60w rad fan*
25w ECU*
3w instruments*
45w horn*
Intermittent loads like the horn, turn signals, brake lights, and even the radiator fan as it probably isn't coming on in those temps, you can leave out of the calculations.
So that leaves the NT riding the highway with low beam on using about 213 watts. I'm not entirely sure what's going on with the front turn signals when in their dim mode, but I doubt they're drawing 42w. (low beam + 10w combined tail + position light + plate light + ignition + ECU + gauges + fuel pump)
Turn on the highbeam for night riding you're now at 268 watts.
438w available - 268w used = 170 watts left over if you're running High Beam
438w available - 213w used = 225 watts left over if you're running Low Beam
If I add up all my heated gear (pants, jacket, insoles, gloves) that comes out to about 150W on highest setting. I typically don't run everything on highest setting, so the actual draw for the gear could be 3/4 or even 1/2 that 150W rating.
Now the common sense stuff. If I'm hooking up some heated gloves, I'd leave the grips turned off. I'm not going to be idling at a stoplight with my high beam, aux lights, and gear set to full blast as alternator output drops with RPM. I've got a cheap Voltmeter fitted, so if I exceed stator output and start draining off the battery I should see it.
Feel free to chime in if my math looks off. Does anyone know the exact Wattage of the honda line grips? I'm assuming it's anywhere from 20 - 50 W. I see a bunch others at 48w, guessing it's the same that would be around 175 watts with pants, jacket, insoles set to high . From my experience, heated gloves are more effective. So even more reason to save 25ish watts and leave the grips off.
i saw some jackets with their own removable rechargeable battery for heating, good enough for 4-8 hours of heat...
Buy CONQUECO Men's Heated Jacket Soft Shell Hoodie Jacket w/Battery for Outdoors and other Fleece at Amazon.com. Our wide selection is elegible for free shipping and free returns.
www.amazon.com
Click to expand...
I think you'd be just fine plugging to the bike, just be smart about it. I did a ride recently in the low 30's, cruising backroads maybe at 4K RPM. I had the jacket around 50 - 75% and the grip heaters near max. High beam used as normal. Was out for an hour or so, and no indication I was draining off the battery. To be a bit more specific, Low on the pants/insole combo was what I settled on. Those two items are rated for around 55W at 100%. My gear, and I imagine most on the market, use PWM as means to control temperature setting. There's three settings on this particular pants controller, so figure "Low" is a 33% duty cycle.
If there's still concern, there's plenty you can do to give yourself more breathing room. Reduce wind with deflectors and high windshield. You could gain 5W by removing the position light. Although I'm not a fan of doing this from a light control aspect, you can free up 40 - 60W by swapping the headlight halogens for LED drop-ins. That's a huge gain, enough to run a garment or two.
Fit a voltmeter to keep an eye on the charging system. The better insulating your outer layers are, the less you'd need the electric heat. If your riding suit makes you look like Randy from "A Christmas Story", you probably don't need the electric gear set to high.
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