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Seeing 12.6V at idle, normal behavior?

Started by aigram, May 17, 2024, 06:33:13 PM

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I'm seeing 12.6V across the battery terminals at idle. With some RPM the reading jumps to ~14V. Is this normal behavior?
I'll just note for what it's worth that I have run an AGM battery for two seasons and the battery seems healthy!
1989 FJ1200 3CV

T Legg

Thats normal. The alternator doesnt spin fast enough at idle to reach charging voltage.
T Legg



What is your idle RPM?

Are all the battery connections shiny-bright where they make cable contact?

The far end of the battery (negative) cable can be corroded where it connects to the bike, too.

Still, that behavior does not sound bad.

P.S. Life is too short, and health is too valuable, to ride on cheap parade-duty tires.