Fully charge to fully dead in 1 night

B

Bobby Joe

Been Around the Block
Quick question potentially (no pun intended). I have a new AGM battery. Strong charge from the store and held nicely at 12V+ for a few weeks without running the bike. I finally got my new petcock in and hooked the tank back up and ran the bike. It was beautiful!! That new battery started the bike with no effort. Once it was warm, it would start instantly! Ooooh, how I have been waiting for that day! But I wasn't sure when I would need to run it next so I shut off the fuel and ran the bike until it sucked the fuel from the carb bowls and died. Apparently, I forgot to shut the ignition off though. Would the battery normally die in just one night? and by die, I mean about 0.66 volts!!! Can I even recharge this or is it too low? If I recall, I need somewhere near a 1.5A charger...only have a 2A...time for the store again :(

Side notes: The bike has LED idiot lights, the neutral and oil light are connected (but do not currently turn on.) The high beam is connected to the wires, but there is no bulb. The blinker wires are not connected to anything currently. The RUN/OFF/RUN switch is permanently on (the wires are twisted together for now). I think the ROR switch being left on may be my draw...but from fully charged to fully dead in 24 hours!?!?!?
 
If the ignition was still on the parasitic draw from the coils alone would kill the battery in a few hours. Sorry man
 
You might try charging it and see if it settles around 12v. I don't know the specifics but I drained a battery to around 4v and it came back. I'd watch the battery while its charging just in case ..
 
Your battery should recover, just charge it up as soon as possible, hit it with high amps at first to get the battery to take a charge, then you can move back down to the recommended charge rate until it is full. if you have a 20A or 40A charger, dont be scared to put it on full for a couple minutes to wake the battery up just dont try to completely charge the battery like that, you will boil it..
 
I have had it on the 2A for about an hour off and on and it is at about 11.8V now. I will swap it over to the trickle charger (0.75v) for the rest of the night and check it before work. So glad it came back. My led acid one didn't.
 
It's capacity will be less, but should still be usable....Lead Acis batteries don't like full discharges at all....

They like fully charged...Get a Battery Tender Jr. from Amazon (cheapest place for them) and leave the battery on charge whenever parked. Long, floating charges also help the battery recover more of it's capacity.

My NH750 AGM battery is 7 years old and still great. My CB360 regular lead-acid is now 2 full seasons old and still great.

Before I schooled myself on batteries, I used to go through at least one battery every 2 years, and often one a year.
 
I did get a BTJ due to what people said on DTT and SOHC4 and I do use it, but this was an overnight accident.

On the battery tender jr note, do I just plug it in and leave it or do I just plug it in every few days?
 
I keep both my bikes plugged in to BT's whenever parked (all the time). The battery in my NH750 was installed in June 2007 and still going strong.

If your battery is not sealed, make sure to check the electrolyte once a month...
 
Depending on the bike and model year you could have also 'cooked' a coil
If it's the 500f in sig the generator could also be 'fried', the 82 would probably have the the potting compound melt out of ignition 'boxes' as well as generator overheat
 
crazypj said:
Depending on the bike and model year you could have also 'cooked' a coil
If it's the 500f in sig the generator could also be 'fried', the 82 would probably have the the potting compound melt out of ignition 'boxes' as well as generator overheat
Click to expand...

By leaving the ignition on? It's a 1971 cb500...no f model here. That would suck hard bc my coils are new.
 
The f means it's an inline four, 500t is a later model developed from CB450 twin.
Leaving ignition switched on can cause all sorts of problems.
You will need to check everything for correct resistance or continuity, check points as they could also overheat causing return spring to go weak
 
I figured you may have meant 500-Four, but I didn't want that argument starting on this thread. Thanks for the warning. I just got done doing all of that...guess I will do it again. Good news is that the bike does still start up instantly. I hope that is a sign of good things and a lucky mishap.
 
If it's starting and running check battery voltage goes up when revved to about 5,000rpm. You should really do an amp test as well. Weak points spring will only show up around 8,000 rpm or more. Points are relatively cheap if you find a problem
 
You must log in or register to reply here.

DTT Light or Dark

  • DTT Light
    • www.jadusmotorcycleparts.com
    www.lostapostle.ca/
    www.sparckmoto.com

    Spread the Love

    Back
    Top Bottom