How do I test the battery?

Does anyone know if there's a specific method for testing to see if the battery needs replacing?

Recently I had the RR wiring harness burn up and the bike stopped charging, kept it on a tender at night so I could keep commuting on it until i replaced it. Replaced the whole RR unit with one from Rick's Motorsport Electric since I figured while I was at it....

anyway, everything seemed just peachy, until like 1400 miles into a 1700 mile trip, when I pulled over at a rest stop, turned off the bike, and when I tried to start it again, nothing. There was no signs of anything else wrong with it, and the meter plugged in was reading a full charge, fuel pump whirred, FI light turned off... but no ignition. I shut everything off, let it cool down for a bit after finally giving up and rolling it into a parking spot, then a few minutes later tried it again and it started right up.

It's still starting now, haven't had another incident, though I've noticed my headlights flicker out more often than they used to when turning the bike over, and think maybe it's a bad battery? How do I test for it? I'm wondering if the bad charging circuit damaged the battery before I fixed it.

I keep it on a tender every night.

 

You need to load test the battery. Unfortunately the larger car/truck load testers dont work for these small batteries. You could take the battery off and go to your local power-sports dealer and have them do it to determine if its kuput or not. Age works against batteries like it does to humans too, so if its older than three years, think aboot replacing it.

Battery may only be the tip of the iceberg btw, electrical connections, grounds, fuse panel, etc could all be adding to the problems...Good Luck...Cheers

 

Basically all four elements of the charging system (battery, RR, stator and loom) need to be in good health. A fault with any one can damage one or all of the others. Something as simple as a loose battery or earth connection can result in the battery progressively draining and leaving you stranded so check the basics first.

Checking out the battery is the vital first step. If you have no idea how old the battery is, then this may help you work out whether its time to replace the battery.

A healthy charged battery without any load will put out around 12.7-13.2 volts. Numbers will drift down as the battery ages. However if you have the constant drain of an alarm system or any other continuing drain to contend with, I would consider fitting a replacement once the standing volts regularly hit 12.8.

As has already been said if you want to carry out a fuller assessment of your battery health, it needs to be done under load. You could take it to a motorbike garage/battery reseller who has proper load test equipment. Or you could try a DIY solution as follows -


To test battery: (original Yuasa type) - remove from bike and trickle charge overnight with a decent Optimate type digital charger until it is fully charged. The digital chargers won't over charge/cook the battery. So next morning ...

- End of charge volts should be 12.7-13.2V
- Connect a load to the battery (any old 21W indicator bulb should provide enough drain)
- Check voltage every 30mins or so and see how long it takes for the battery volts to drop to 12.3V
- Less than half hour = Totally dead battery - bin it!
- About one hour = Virtually dead battery - needing replacement now!
- More than one hour 30 = battery is still serviceable - but will need replacing soon
- More than two hours = Good battery.

Hope that helps


SkiMad

 

Hook up a voltmeter to the battery and measure the voltage with the key off and then turned on with the headlights on high beam. Then watch the voltage as you hit the starter button and see how low the voltage gets pulled. A strong battery can hold up the voltage under load and supply the current whereas a weak battery won't.

The starting issue on your trip sounds like a loose or bad connection in the harness. Also make sure your tender is not overcharging the battery and 'boiling' off the electrolyte-- low water can make a battery weak.

 

Or, you may have a bad starter, starter switch, bad connection to starter. You did say "nothing" happened when you tried to start it. Am I the only one who ever used a "starter stick" AKA: A long piece of wood in which you tapped on the starter while yelling to your girlfriend - "Now"! Ah... Good Times!!!

 

a cunning sized hammer works too, kinda reminds me of a funny named band, "the Cunning Stunts."

could be a starter issue too, but based on op's flickering headlights, would rule it out, but like I sed before, "kind of an open season and pandoras box of stuff to check oot!"

 

ridevfr is correct to rule the starter out, i most heartily agree.

Starter motor failures are very rare, whatever the mileage. One of the parts Honda's electrical suppliers do damn well. Only occasionally wear out brushes (easy replacement) on bikes with other starting problems. Owner abuse can lead to starter failures when the starter button is continuously ON for more than a few seconds without rest periods, owners manual specifies 10 seconds max. Otherwise, overheating = damage, ruin, $$$, and a backache to change.


To return to op, best way to test a battery is by REPLACEMENT imo. You can measure it with meters, but that batteries can do some strange things you learn with 'sperience.


Hey, i used a starter stick too on a couple of cars !

 

did a brush replacement and a good cleaning on my bike and no more hot start issues and the bike sounds like the new ones from the dealerships during starter engagement.