failed battery?

[Rein]

Hey guys, so I finally got the 650 running, runs like a dream, however, If I leave it for more than 24 hours without running, the battery dies/insufficient power for starting. The charging system is fine, it stays at 13-14 volts when running. I let the bike run for 10 minutes, hoping that it would charge the battery, but I guess that's not enough to charge? Should I pick up a trickle charger? Or a new battery?

[Nessism]

There is no way for us to know. How old is the battery? How long did it sit in the discharged state? At any rate, you should have a trickle charger so it wouldn't hurt to pick one up and see if that takes care of the problem.

[Rein]

There is no way for us to know. How old is the battery? How long did it sit in the discharged state? At any rate, you should have a trickle charger so it wouldn't hurt to pick one up and see if that takes care of the problem.

Battery was new when it was put in, it sat for a year and a month or two. So am I correct in thinking that the charging system is not sufficient to recharge a dead battery?

[SqDancerLynn1]

If it stays at 13-14 volts while running . Probably a bad battery. CHeck the battery voltage with the bike off and again when running. Charge it up for 6-8 hours before checking it...Take it to AutoZone or some place and have it tested.

[Nessism]

Battery was new when it was put in, it sat for a year and a month or two. So am I correct in thinking that the charging system is not sufficient to recharge a dead battery?

When a battery sits without a charge for an extended period of time, the plates sulfate and nothing will bring them back. There is an outside chance that the plates in your battery are not totally destroyed, so it's worth a try to charge it, which will require a charger of some sort unless you want to go on a ride of several hours.

[Rein]

That's what I thought. What should the voltage be at when the bike is running?

[BassCliff]

Hi Mr. Rein,

I suggest reading the Stator Papers.

At idle you should measure about 13v at the battery. At 4000-5000rpm you should see around 14.5v at the battery.


Thank you for your indulgence,

BassCliff

[Nessism]

That's what I thought. What should the voltage be at when the bike is running?

EDIT: Cliff posted while I was typing...

Should be in the range of 14 - 15.5 at 5000+ rpm. This is just a guestimate off the top of my head - the actual numbers are in the service manual (and I'm feeling too lazy to look it up).

[Rein]

I guess I should pickup a voltmeter gauge for the bike?

[focus frenzy]

EDIT: Cliff posted while I was typing...

Should be in the range of 14 - 15.5 at 5000+ rpm. This is just a guestimate off the top of my head - the actual numbers are in the service manual (and I'm feeling too lazy to look it up).

15.5 is way to high, 14.2 is the best peak voltage for long battery life.
charging to 14.5 volts will cut into light bulb and battery life span.

[waterman]

Rein, I would check voltage of battery after charging, then after it has sat overnight. If the battery is holding a charge, it shouldn't lose any appreciable voltage overnight. A decent battery will be fully charged near 13 volts, it may be discharged at 12.5 or less, YMMV. A bad or "worn out" battery will maybe charge to nearly 13 volts but will lose charge quickly without a load being applied.

[Rein]

Also, I'm fairly sure it's there's not battery drain going on, I've checked all the wires in the harness, and they don't look 28 years old, they look almost new!

Anyways, I'll check the battery after charging it today, then in the morning.

This might be a good reason for me to finally pick up a sealed battery.

[Nessism]

15.5 is way to high, 14.2 is the best peak voltage for long battery life.
charging to 14.5 volts will cut into light bulb and battery life span.

You may be right but Suzuki lists 15.5 volts as acceptable for some reason.

[eddiev]

I would try putting an ammeter on it to see if something may be draining it. Anything more than a couple of milliamps shouldn't be. If there is no drain I'd suspect the battery being that it sat so long uncharged.
Eddie V

[posplayr]

Ed

You may be right but Suzuki lists 15.5 volts as acceptable for some reason

That is how it work .

Just not very acceptable.

FET Shunt, Fet Shunt, FET Shunt