stupid (?) question about battery charging

Nielsen · Jan 20, 2015

Please indulge me if this is a stupid question. I've only had my Commando for a year now. I'm a newbie.....

Can I use me regular cheap-and-cheerful battery charger from 'Canadian Tire' (a DIY store here) to charge my positive ground Commando battery when the charger is presumably designed for negative ground car batteries? If yes, can I assume that the positive lead on the charger does indeed go to the positive terminal on the Commando battery? I won't do anything 'till I hear from you experts.

Hobot · Jan 20, 2015

Duh yep dumb question as all batteries have same polarity, red+ teriminal postitively emits negative electrons while the other neg- terminal accepts the negative electrons back. Just Always hook + to + and - to - just like jumping a car battery and charger will work fine.

Rohan · Jan 20, 2015

Yes, all you need to do is ensure that the charger +ve clip is on the battery positive, etc, and you are away.

Best if you disconnect the battery from the cycle, as wise heads do.
No need to load all the Lucas bits when not needed.
Although not absolutely necessary, it is best...

P.S. Not knowing this charger, if it is one of the big powerful types, just watch that it can't/doesn't overcharge the battery.
Some just keep charging until they essentially boil the battery dry.
While unlikely, its not impossible....

Hobot · Jan 20, 2015

btw the fuse should be sized small enough if ya did hook a charger or battery wrong it blows and nothing else. It helps to think of Commando red wires as positive wires feeding every item then returning by the various color negative battery ground wires.

Torontonian · Jan 20, 2015

Crappy Tire charger goes positive to pos. bat. post and neg. to neg. Just make sure the ignition does not get turned on accidentally whilst charging. I pull the keys out to prevent children or drunks or myself from turning anything on whilst charging. Don't overcharge ,you have a crappy tire voltmeter to know when 2 stop ? They sell intelligent chargers now 2. :|

gtsun · Jan 21, 2015

No such thing as a stupid question, not asking is stupid. Don't feel bad, when I went to pick up my BSA 441 years ago the owner thought he would do me a favor by charging the battery. He thought positive ground meant he should put the + from the charger to the - of the battery.. When I got there he had this bad look on his face and said he had sent the bike to his mechanic to be "fixed"... After talking to his guy I said "stop working on it" I had him send it to a guy I knew who then repaired the damage this "mechanic" did. Ask the question, allways ask. I have asked some stupid things here & probably had some laugh at me but it's better then Fu#*%ing something up.

texasSlick · Jan 21, 2015

Rohan said:
Yes, all you need to do is ensure that the charger +ve clip is on the battery positive, etc, and you are away.

Best if you disconnect the battery from the cycle, as wise heads do.
No need to load all the Lucas bits when not needed.
Although not absolutely necessary, it is best...

P.S. Not knowing this charger, if it is one of the big powerful types, just watch that it can't/doesn't overcharge the battery.
Some just keep charging until they essentially boil the battery dry.
While unlikely, its not impossible....

All good advice...most car battery chargers have a 2 amp or "trickle" charge setting....use that. Note that the charge rate is initially high and drops as the battery comes up to full charge. Disconnect the charger when the rate stabilizes.

Slick

dynodave · Jan 21, 2015

Nielsen said:
Please indulge me if this is a stupid question. I've only had my Commando for a year now. I'm a newbie.....

Can I use me regular cheap-and-cheerful battery charger from 'Canadian Tire' (a DIY store here) to charge my positive ground Commando battery when the charger is presumably designed for negative ground car batteries? If yes, can I assume that the positive lead on the charger does indeed go to the positive terminal on the Commando battery? I won't do anything 'till I hear from you experts.

The main reason for caution is for preserving the regulation zener diode. When the charger & battery get over 14 VDC ( and it will eventually) the excess voltage/current will potentially cook the zener. For this reason the battery MUST be disconnected from the bike (wiring) by pulling out the fuse...and hooking up directly to the battery only.

DogT · Jan 21, 2015

Yes, best if you disconnect the battery, there should be a fuse right off the - terminal, just remove that and attach the charger - to the battery -, leave the + terminal as is. Better to get a 'smart' charger' if you don't pay attention to how long its been hooked up.

ommief · Jan 21, 2015

Maybe a good time to consider this mod: http://www.gabma.us/elec/fuse_holders.pdf
I've done it to my '69 Bonneville as well as the Norton. Makes charging a breeze and it's a cinch to obtain & carry spares.

Nielsen · Jan 21, 2015

Thanks very much, everyone, for your help. The battery is out of the bike, so no problem there. Cheers.

Torontonian · Jan 21, 2015

Fuse holder Conversion article was a nice easy informative read. The eye opener for me was the installation of it on the ground point. Looks like another winter mini project to do. No more fragile glass tube stuff. :shock:

baz · Jan 21, 2015

Don't ever be afraid to ask any question nobody is born with all the knowledge and as any engineer/mechanic and just about anyone who actually does anything will tell you "its better to ask a stupid question than make a stupid mistake" i once connected up my battery round the wrong way on my A65 lightning i was only 18 i realized my mistake and re connected it the right way but un be known to me it had burnt out the zenor diode i did get over a 100 miles or so before it cut out dead right in the east end of london i had to walk for miles to find a bike shop where i bought a new battery and this got me home,it was a sharp lesson but i've never done it again!! ,,,,,,,,,,,,,,baz

Torontonian · Jan 21, 2015

Yes it's fun to ask what we ourselves perceive to be stoopid Questions. My banker said that yesterday , and after re-arrangements the MK 111 is going to become a new reality . Feel good , leg slow healings , off to Mexico 10 wks. recovery. Buy a top of the line ignition. :wink: :|

Hobot · Jan 21, 2015

Ah man ain't yoose guys been through hazing phase of fraternities where ya get some kix teasing newbies? I went more freak for the better rush, so have more than once hooked wrong bike wires to battery but not a charger, which most have some alert and shut off safety if that happens. Never want to see any smoke leaks.

MikeM · Jan 22, 2015

Superstition but I disconnect the battery from the bike while charging. I am on the tender for the winter with the fuse pulled.
Cant hurt.

Torontonian · Jan 22, 2015

Good advice. Protect your electrical system. I purchased the new optimate with reverse polarity detection with shutoff to warning light display before damage. But pay attention to polaritys always. This not be a modern bike. :|

Nielsen · Jan 22, 2015

No worries, Hobot. I am now hazed..... and not insulted.

Hobot · Jan 22, 2015

Alrighty Nielsen, I'm not as much nuance as Commando learning curves. My cockyness bit my ass on this subject a few days ago, my modern was intermittently cutting off last few rides I'd 'fix' by bumping battery box so thinking just loose terminals again, lead to starter relay clicking but no spin to find a fuse in relay blown so replaced and then main fuse blew so gave up stumped so far to do something more productive. Complained to wife who instantly said - oh ya got a short, ugh. Smart gal I couldn't pay to ride on a motorcycle.

stupid (?) question about battery charging

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