At one point BMW was including a 3 amp battery charger with the purchase of a new BMW motorcycle. I'm now an owner of two of these gems/relics and I don't remember the selling points. They look to be fairly good quality. But does anyone remember are they just straight battery chargers? Or did they have any thing like a trickle charger mode? Some time ago I was under the impression there was an issue with over charging if you left them on like a trickle charger. Here's a photo

A charger of that vintage would not have a maintenance charger feature. It would be 3 amps or nothing.

JJeferies, Is it 110 or 240volt powered?  If 240volt are you interested in selling one?  Cheers, Alan in Oz

What Rick says. The output will be completely uncontrolled.

A neat heritage item that would enhance a person's shop (provided they have room).
If supplied to the North American market the input should be 110 -115 V ac.
The output if the unit is not too old should be 12 V but perhaps it has a 6 volt output as well!
Unique item.

P.S. The picture clearly shows 120 V ac input and only a 12 V dc output . As well it shows that it was made in the USA.

Those old units are straight charge, 120Vac and 3 amps continuous output - as it says clearly on the front label. No pulse charge for anti-sulphation of FLA, AGM and the like, but ideal - somewhat ironically - for lithium ion batteries if you only use them for a few minutes to verify the condition of the battery. These were the bomb from the late 1970s through the early '90s. The part numbers, BMWNA 'accessory' numbers, 95 61 1 250 700 & ...800, were discontinued long ago.

There are a few listed on eBay...

US eBay BMW charger

eBay US BMW charger

Charger BMW US eBay

jjefferies wrote:. . . I don't remember the selling points. They look to be fairly good quality. But does anyone remember are they just straight battery chargers? 

The selling point was that it would charge the battery if the battery hadn't been discharged so frequently that the battery was ruined. Attach the cables, plug in the charger then unplug it when the needle quit descending the scale. The downside was that if attention wasn't paid to a timely unplugging, overcharging could happen. It worked fairly well for many of us in an era when our attention wasn't distracted as much as it can be today. 

RicK G wrote:A charger of that vintage would not have a maintenance charger feature. It would be 3 amps or nothing.

Well, actually that's sort of what lead to the question. The meter on the front shows the charge rate decreasing until it's just showing. And I vaguely remember someone years ago complaining about leaving one on all winter and having unexpected results.

I assume they're usable as chargers.

Snashall wrote:JJeferies, Is it 110 or 240volt powered?  If 240volt are you interested in selling one?  Cheers, Alan in Oz

They'd probably like the environment. Unfortunately they both specify 120volt input for 12 volt output.