Charging a battery

[Fast Eddie]

I think it could also be a fuel issue as it tends to sound like it's running on 3 cylinders when it hasn't been started for a few days for the first 15 - 20 seconds or so.

this could also be electrical? not enough batt power to produce a proper spark *especially after cranking the motor from cold, until the alternator takes up the load or something...

im just babbling

[SMOKEU]

I just removed the battery from the charger after a 1.5 hour charge, and I tested the voltage with a multimeter and it read 13.73V. I then connected the battery back up to the bike and tested the battery immediately without turning the ignition on and the voltage read 13.55V. I don't have any aftermarket goodies connected to the battery. Is it normal for the voltage to drop like that on a carbied bike?

It is a cheap Chinese multimeter off Dealextreme, but it hasn't given me any reason yet not to trust it.

[neels]

Yeah, at 2.5A it's not a quick charge and more for overnight charging, too.

Given that most bike batteries are around 8-12Ah, 2.5A is not a slow charge either. Normal slow charging rate is 1/10 of capacity, overnight at 2.5A into a 12Ah battery is boiling the crap out of it, unless it is a smart charger.

I just removed the battery from the charger after a 1.5 hour charge, and I tested the voltage with a multimeter and it read 13.73V. I then connected the battery back up to the bike and tested the battery immediately without turning the ignition on and the voltage read 13.55V. I don't have any aftermarket goodies connected to the battery. Is it normal for the voltage to drop like that on a carbied bike?.

Volts don't just run away by themselves, even if it's only 0.2V the battery shouldn't drop that much in no time. You need to put a current meter in series with one of the battery leads and see if there is anything being drawn with the key off.

If you need a hand give me a shout, I'm semi qualified to bugger about with things like this.

[Akzle]

Volts don't just run away by themselves, even if it's only 0.2V the battery shouldn't drop that much in no time. You need to put a current meter in series with one of the battery leads and see if there is anything being drawn with the key off.

If you need a hand give me a shout, I'm semi qualified to bugger about with things like this.

go and do it. he's been told at least once before.

[CookMySock]

If the battery is really old it is possible it will have a really high internal impedance. If this is the case, the charger may push the terminal voltage outside of the safe range for electronics on the vehicle. If the battery will turn the engine over whatsoever, it is very likely this is NOT the case, and the charger maybe be connected without disconnecting the battery. However, if the battery is utterly dead stone flat (tests less than 9 volts on meter), or it is very old or has been lying around for months and months, I would definitely suggest you disconnected it from the vehicle before connecting any type of charger.

[tigertim20]

The bike has minimal electrics compared to a modern bike (it's carburetted) so it's a bit of a worry. It still cranks quite well after a week, but not quite enough to start it. The fact that the headlights are hard wired on when the key is switched on is also part of the problem. Usually it's fine after a week if I disconnect the headlight plugs. I might cut the headlight wires and put in a switch so I don't have to disconnect the plugs every time.

cant be bothered reading the whole thread . ..
get a battery tender, they arent very expensive. I also saw the other day, a solar powered battery tender, so even if you store the bike in a shed that doesnt have power, or even under a cover, its easy as pie to set up for trickle charging when not being ridden.

if it dies after 5 days enough to not start the bike, Id get it tested. most battery places will do a test for you on the spot free of charge and they can tell you if its at the end of its life

[caseye]

Then go and buy one of Ed's beauty little batteries.
Something wrong if any battery won't crank a bike after a few days.
Coal Burners been dormant for the last three months, starts and runs easy every 4 - 5 weeks.
Musta put her back together proper then I reckon.