Flat battery then not flat?

[hawk2993]

Hi Guys,

I rode for about 40 minutes to a place. I was in there for about 1.5 hours, when i came back out, battery was dead flat, so i did a running start and rode home fine, once i got home, i turned the bike off, then turned it back on, it started up just fine, the battery was charged all of a sudden.

I know the stator is fine, had it rewound last year, and it did recharge the battery. Could I have a bad battery or regulator?

I'm going to see if it'll start later tonight.

Thanks.

[Neosophist]

http://www.400greybike.com/docs.htm

follow the charging system checks. first document in the document library to help troubleshoot the battery.

Its cold this time of year, if your riding with lights on it could easily drain the battery enough not to start, especially if its not used often and not charged up regularlay.. charging a flat battery with the bikes genertor will put more strain on it than is good and can lead to premature failure.

dont rule anything out until youve re-tested it.

[Icemaestro]

Loose connection at the rr or battery/somewhere? Since it charged again fine on the way home...

[hawk2993]

Going to get a multimeter tomorrow and try it out. I'm in Sydney btw so it's currently really hot lol.

I started the bike up again and it started up great...but the lights are veryyyyy bright, I suspect its running at too high a voltage? Anyway, will confirm with multimeter tomorrow.

[Neosophist]

Going to get a multimeter tomorrow and try it out. I'm in Sydney btw so it's currently really hot lol.

I started the bike up again and it started up great...but the lights are veryyyyy bright, I suspect its running at too high a voltage? Anyway, will confirm with multimeter tomorrow.

Ah..

NEVER ride the bike if you suspect that, you can easily kill a new battery in 5 minutes if its over-charging.. if its the case then probably its already knackered.

Not only that but high voltage (worse than low as that will lead to a flat battery) can also fry the igntion box and melt wires.

hope you get it sorted.

[hawk2993]

Going to get a multimeter tomorrow and try it out. I'm in Sydney btw so it's currently really hot lol.

I started the bike up again and it started up great...but the lights are veryyyyy bright, I suspect its running at too high a voltage? Anyway, will confirm with multimeter tomorrow.

Ah..

NEVER ride the bike if you suspect that, you can easily kill a new battery in 5 minutes if its over-charging.. if its the case then probably its already knackered.

Not only that but high voltage (worse than low as that will lead to a flat battery) can also fry the igntion box and melt wires.

hope you get it sorted.

So i did the test today, 13.58 volts at 5500 rpm, 12.6-8v at idle. and the battery itself is 13.01 volts with everything off. So everything seems fine....hmm......I don't want to ride the bike in case I really do some serious damage. I'll try turning the ignition on for 15 minutes and see if the voltage drops below 12v to see if its the battery?

[bikemonkey]

Those readings actually look a little low....

[hawk2993]

I turned the bike on (I didn't start it), and within 5 minutes the battery was below 12v. Does this indicate bad battery? Or was I supposed to start the bike and let it idle for 15 minutes checking to see if the voltage of the battery would fall?

[hawk2993]

Also, tips on removing the connector from the rectifier? It's not coming out!

[bikemonkey]

To load test the battery:

Fully charge it,
Turn the ignition on,
Do not start the engine,
Put the full beam on,
Monitor battery voltage until it drops below 11V,
A good battery should get between 20-30 minutes.

As for the rectifier plug isn't there something you push in to release it?