Charging the battery?

[slofox]

Grrrrrroarsnortrantrave....

I know there is a thread in here somewhere about charging a battery in th' bike but I'm damned if the search function will tell me where it is...

The question: Do you disconnect the battery to charge it or just leave 'er in there all connected up? Oh and why would be good too...

I've always charged batteries in place, connected an' all, but what with all the modern day doohickory electromicktrickery in there..?

Waddaya reckon then?


ps anyone else find the search function "less than ideal?"

[scumdog]

Had to charge the XN85s battery a couple of days ago - completely flattened it when I left the ignition on.

Just hooked up my 'olde worlde' 60's battery charger to it for about 5 hours and it was completely recharged, never disconnected the battery but did make sure the ignition was turned off.

[slofox]

Had to charge the XN85s battery a couple of days ago - completely flattened it when I left the ignition on.

Just hooked up my 'olde worlde' 60's battery charger to it for about 5 hours and it was completely recharged, never disconnected the battery but did make sure the ignition was turned off.

Man after me own heart...

Before I posted this thread I had already put the charger on for an hour without disconnecting the battery...thought that if the elcetronics went BANG I might at least know why after the event. But it didn't go bang anyway...all seems to work fine...

And no the battery wasn't flat, just down a bit from running millions of tests to see why a speedohealer will not work in my bike...I think my case has become a personal challenge to the man at Speedohealer Electronics...been going on for weeks now...

[neels]

I always charge the buggers connected, because I'm too lazy to find the tools in my shitfight of a garage to disconnect them.

There shouldn't be any any electronicy dohickies connected if the ignition is switched off, so can't see why it would make a difference really. The only thing I would suggest is connecting the charger before you plug it in, they can have quite a high open circuit voltage if you switch them on first, so if it was possible to damage anything it would be the 40+ volt spike if you connect it powered up.

[Spuds1234]

I have a bitch of a time reaching both terminals of my battery to disconnect it when I charge it.

So I only disconnect one terminal.

On and older bike I would just leave it connected up. On a new bike with fancy electronics I dont understand I would rather disconnect it because I dont know how fussy they are.

[slofox]

I always charge the buggers connected, because I'm too lazy to find the tools in my shitfight of a garage to disconnect them.

There shouldn't be any any electronicy dohickies connected if the ignition is switched off, so can't see why it would make a difference really. The only thing I would suggest is connecting the charger before you plug it in, they can have quite a high open circuit voltage if you switch them on first, so if it was possible to damage anything it would be the 40+ volt spike if you connect it powered up.

That's pretty much my logic as well. Didn't seem to do any harm anyway. But yes, I always connect before turning it on...

On a new bike with fancy electronics I dont understand I would rather disconnect it because I dont know how fussy they are.

Yeah. Which is why I asked the question. But it seems OK anyway...like the man says, as long as the ignition is off, it should be sweet...

[tri boy]

At least one terminal should be disconected.
Ignore this at your own risk.
A charger that has the ability to dump high amperage, (especially solid old ones with faulty electrics internally) can damage sensitive electronic items in cars/bikes/out boards etc.
"Are you feeling lucky? well are ya punk" (poor Clint Eastwood impersonation)

[Owl]

My bike lives on a charger, in fact it's hard-wired with an inline fuse. No need to even remove the seat and never had an issue.

I used to always disconnect batteries at work, but that often caused issues with more modern vehicles (alarms/radios). I asked our resident sparky/mechanic if it was ok to leave connected and he reckoned it'd be fine. He said "just don't try to start it while connected". Since then (last 10 years), we haven't had an issue with connected batteries.

If you're still worried, remove the battery completely from the bike, as you'd have more chance of finding a faulty battery that will swell and leak, whether terminals are connected or not.

[T.W.R]

There is a reason why manuals say remove battery from machine before charging
Some manuals even have Highlighted/boldly written warnings saying CAUTION: Never charge a battery while still in the machine as damage may result to the battery or regulator/rectifier.

[nodrog:Me]

When using a battery charger I always disconnect at least one lead to break the electrical circuit on the bike.

Just because the ignition is turned off doesnt mean the bikes electrical system is disengaged. Have you ever noticed the electric fans on a buell? Or how a modern speed triple sounds like its sending a fax about 30 seconds after turning the ignition off, as it runs its diagnostic check? Its not solar power these functions run on.

Fanny

[scumdog]

I hear what they're saying above but MY take is: if the key is off and you connect the charger to the battery first THEN turn it on at the wall there should be no surge of power to anything..

But I haven't got too much in the way of fancy elektrickery in anything I own...

[davereid]

Luck

Is what you need if you charge a battery while it is in the bike. Some bikes will be better in this regard than others but here is why you should remove the battery - or at least the earth lead.

(1) Overvoltage

The electrics in your motor cycle are designed for nominal 12v DC. But the peak voltage out of your battery charger will be higher than that.

Over 20 volts for many chargers.

Maybe your electrics are good enough to cope. Maybe your battery will draw enough current that the bike will be protected from the chargers peak voltage.

Maybe not.

(2) Shunt voltage regulators
Many motorcycles have shunt style voltage regulators. They are very simple devices that take excess electrical energy and turn it into heat. This draws current from the alternator, causing its output voltage to drop, thus providing voltage regulation.

But when you connect a charger, the shunt regulator will attempt to regulate the charger, instead of the alternator.

Maybe it will work.
Maybe it will get too hot and fail.
Maybe the charger will get too hot and fail.

(3) The "Battery Tenda" and similar products
These chargers have a couple of special features that mean they are pretty safe to use with battery. Firstly they have a low peak open circuit terminal voltage. This means they don't do problem (a). Secondly they have a limited output current so they don't do problem (b).


So, its luck. comes down to your bikes design, the charger design, the condition of the battery.

Good Luck.