Stator Output and Charging System Performance

How-to's pertaining to the electrical system, ignition, lights and battery
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TonyKZ1
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Joined: Tue Nov 12, 2013 12:15 pm
Location: Marble Hill, MO. U.S.A.

Here's what I had bookmarked from an earlier post by @gliderpilot. I can use a 65W heated jacket liner and a pair of 20W heated gloves or heated grips and it works okay. I've also replaced my headlight bulb with a LED model to free up some more electrical power, so I wouldn't drain the battery during this cold winter's commute. The post is below.

All US models, according to my manual...

No load, regulated voltage: 14.3 to 15.3 volts, at 5000 rpm.
Nominal output: 14 volts, 20 amps, at 5000 rpm.
Stator coils resistance: 0.32 to 0.48 ohms, at 20 deg C/68 deg F.

The output equates to 280 watts (14 times 20), which is not bad going for our little bikes...
I roughly worked out that the current draw for running at night (at least on a '95 UK model), ie: headlight full beam, running indicators occasionally, braking, etc, was about 10 - 12 amps, leaving roughly 8 amps max to play with. That would allow an additional 90-odd watts (8 times 12 approx) available for heated vests, spotlights, etc.
(My caveat is that THAT was a rough calculation, and would of course drop when idling, so don't take my figures as gospel: check your own bike, folks!)
1997 Yamaha Seca II - mostly stock, Racetech upgraded forks, FZ6R rear shock, Oxford Adventure Style Heated Grips, a Scottoiler vSystem chain oiler. My Mileage Tracker Page.
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