Club 80-90 Forums

Got a couple of motorcycle 12v batteries and wondered what the 'resting' voltage should be? I'm asking because I've got readings of 17.2 ish from all of them. I suspect my (very cheap) multimeter.

Just checked my GSXR 1000 12.56v

SEVENTEEN?
Definitely duff meter.

They'd have been boiling away merrily on whatever charger took 'em that high, apart from anything else.

It is possible to see 13.5 or more just after taking off charge but 17.2 volts
Basically all batteries will hold on to a residual (high reading) just after being disconnected from a charger, however, leave them for a few hours and this soon drops to a 'nominal' standing state of around 12.6 volts (lead/Acid) and slightly higher (12.8 - 12.9 volts approx) for newer sealed Calcium/Silver types.

Martin

Cheers all. suspicion confirmed really.

I've never seen a 12v battery measuring over around 13.5ish (you normally don't get over 14v going in from the alternator)

I had one read 16+ v after a battery charger malfunctioned - it didn't do it much good as it was on for quite a while. Apparently that model of charger had several reports of that happening.

The ~17v reading is on three batteries (its an Aprilia RSV1000 so needs 'em) so I imagine it must be the meter.

Quick update. It's a digital meter and the battery was dead so put in a new one and getting a sensible 12v+ reading. Never had this with my old dial meter.

Digital meters can often give strange results when battery dying