charging reading 17+volts

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zed88

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HI Guys,

Friday I ran the bikes battery completely down by leaving my heated grips (fuse block and relay coming!). I jumped the bike off a co-workers car (did not turn on his car) and it ran ok. I put the battery on a trickle charger which did not work, and then purchased a new battery and charged that using a 2amp charger overnight. When testing the old one it tested bad (supposedly new, but I had no way to check the prior owners info, and I think he fibbed about something else so..). The new one is reading 13.8 volts when fully charged. I put it on the bike, and now the charging system is showing 17 volts! Is that normal? My other bikes never show more than 14.5. Where should I start tackling this? Thanks

Eric

*edit*

I just rechecked with the bike warmed up and now we are at 15.5. Does this sound correct?

 
Last edited by a moderator:
Your charging voltages should not be that high. I would suspect that all of the electrical hijinks have damaged the regulator/rectifier which limits your system voltage.

It could have been damaged by the previous owner, and the high system voltage killed the "new" battery he installed to replace his dead battery, also killed by the non-working-regulator.

 
Your charging voltages should not be that high. I would suspect that all of the electrical hijinks have damaged the regulator/rectifier which limits your system voltage.

It could have been damaged by the previous owner, and the high system voltage killed the "new" battery he installed to replace his dead battery, also killed by the non-working-regulator.
I'm with slappy on this one. :clapping:

 
A fully charged battery should not measure 13.8 volts -- that's too high. But, you may have measured the voltage too soon after disconnecting the charger.

Fully charged the battery should read 12.8 to 13.1 volts after being disconnected from the charger for at least one to two hours.

The FJR's charging system provides a regulated voltage of 14.2 to 14.8 volts for normal loading. If you're measuring higher voltages something is wrong with the rectifier/regulator.

 
Are you sure your voltmeter is correct? Try a different voltmeter, or check the reading on your car battery or some other known good battery for comparison.

 
Voltmeter was flaking out. Put it up against the fluke meter and its dead on around 14.5. I also switched batteries with a nice one I had in my vstrom (known good, replaced about 3 weeks ago) and it fired right up with no hesitation. I'm thinking I just got a bad battery. I'm going out for a ride now so lets see if we get stuck again. I was scaring myself reading up on stators, and starters, and rectifiers etc.

 
Turns out I got sold a bad battery. I figured that was rare, so I discounted it in my troubleshooting process, but it was definitely causing the trouble. Time to go get a new battery! As usual good advice here :)

 
Turns out I got sold a bad battery. I figured that was rare, so I discounted it in my troubleshooting process, but it was definitely causing the trouble. Time to go get a new battery! As usual good advice here :)
Way back in the dim mists of time.............. I was trained as an electrical tech in the RAF. One of the first lessons that was hammered into us was check your test equipment BEFORE you do anything else. Good outcome and (hopefully) lesson learned! :rolleyes:

Don

 
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