Forum

[Chucklebus]

Hello Peeps, I would like to upgrade my electrics to 12v.
Has anyone done this and had any problems???

[Bullet Whisperer]

Easy - especially these days, with Boyer Powerboxes and the like available to take the place of rectifiers and zener diodes [which of course will also do the job if you prefer]. Just join the dark green and mid green [green/blck and green/yellow] wires together and treat as one wire going to the powerbox. the light green [or green/white] wire goes to the other connection on the powerbox - both alternator wires on the powerbox are yellow and can be connected either way around. You will now have 12 volt D.C. coming out of the powerbox red and black wires, to supply your electrics. You will need to change the bulbs, but the horn will be ok.

[Mark M]

Paul, these models have an 'Emergency Start' position on the ignition switch, does this need to be disabled in the scenario you outlined?

REgards, Mark

[stinkwheel]

Obviously the bulbs will need to be changed. I'm not sure if the original condenser and ignition coil will be ok??



Wiring will be fine because it's carrying less current.

[Bullet Whisperer]

The most similar machine I converted to 12 volt was a twin switch Tiger Cub. If I remember, I just set it up to use the ignition 'on' position, the 'Emg' position became redundant. No battery was used, 12 volt coil, as Stinkwheel says and a 'normal' condenser - I wasn't aware they had a voltage?. The powerbox has a built in capacitor and stores enough current to give one brief 'beep' from a horn - or it did on this machine and starting was usually first kick, or, at very worst, second kick, although it could stall if idling with the lights on.

[Adrian]

Long time ago I converted my old BSA C15 to 12V much as Bullet Whisperer described, only with a separate rectifier and zener diode and (well it was 1977). The coil I used was an old 12V car coil from the local scrap yard, the condenser was the original on the 4CA points plate, it started and ran fine. The horn didn't sound totally happy but still worked. The 6V battery will have to go, but if the existing alternator is still healthy you can run the bike battery-less with a suitable capacitor (there was another thread about this recently). If you go down the Boyer Powerbox route for your regulator/rectifier it already has a built in capacitor which will let you do this.



Mark, the emergency start position on the original ignition switch is no longer used in this case, as all the alternator's output is now permanently routed through the reg/rectifier.



A.

[OldBoy67]

And don't forget the ammeter if you have one fitted.

[OldBoy67]

And fit a main fuse whilst you are messing around with the battery.

[Mark M]

Ammeter will be fine, it measures amps not volts!

REgards, Mark

[stinkwheel]

I don't know about the condenser either but I tought it worth mentioning to see if someone does know because it's effectively a capacitor and I know some types of capacitor explode if they go over voltage.