Specialized E-Bike BMW Charger


Well-Known Member
OK, it's possibly been discussed regarding portable charging, Sine wave DC-AC-DC vs DC-DC, etc., etc.
Bottom line is I'm asking for some possible help.
I recently picked up a Specialized BMW 12v charger that was provided with the BMW/bike combo a few years ago.
I think it's not working. Maybe.

Got it, plugged it into my 12v car cigarette lighter, it lights up, when I plug the Rosenberg adapter to my Vado 5.0 battery the charger light flashes red and the battery flashes.
Much like when the battery flashes when plugged into a 120v AC plug.
The odd part is the physical "brick" is flashing like it's turning on/off, on/off.
But the charger itself never ever flashes (home A/C version), it's either red while charging or green when fully charged and then no flashing occurs. THis portable charger, the brick flashes all the time.

So, I tried it while driving, left the end of the bike ride with 74%, all lights flashing, got home 40 minutes later, still flashing at both ends, however battery is now 85% charged.
Should I just forget it, get the Samlex 300 Watt Pure Sine Wave Power Inverter - Model PST 300-12 and forget the 12v BMW charger or am I missing something?
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Stefan Mikes

Well-Known Member
Brwinów (PL)
Very interesting. The LED in the portable charger might be flashing, why not (it could be designed that way)? I think that the portable charger might really work for you. (Never heard about that charger before).