6 volt to 12 volt conversion, do the wires need upgrading?

[Eddieb]

I've got an old Ducati 250 which I'm slowly working on restoring and it's a bit of a bitsa. One of the things thats apparently been done in the past is convert it from 6 volt to 12 volt, it has a 12 volt regulator/rectifier and takes a 12 volt battery, but the wiring loom has been absolutely butchered. For example there's sections of the loom where every wire is green and looks suspiciously like housing wire, joined to the original loom with chocolate block connectors.

So I'm going to have to redo the loom and I've found I can buy ready made looms online, but they are designed to run with the original 6 volt system.

So my question is, can I run 12 volts through the stock 6 volt wiring loom or will I need to rebuild the loom with heavier grade wire? I don't want to let the magic smoke out of the loom.

Here's an example of the ready made looms: http://www.ebay.com/itm/Cablaggio-pe...item4ab3943ce8

[nadroj]

No prob with the loom as 12v requires less sized wiring because the same wattage bulbs will draw half the amperage. (Watts = amps x volts)

[mossy1200]

when voltage doubled current to do same job is halved and cable thickness will prob be 1mm multi strand anyway on new harness for most things.

How is the alternator.Has it been upgraded also for battery charging 12 volts.It may be the alternator charging cable back to the battery might want to be bigger.If you bring it round after you replace harness ill current test the cables and make any larger that you need(without strip connectors).

[Subike]

I use to do 6volt, to 12 volt conversions on VW beetles, Morris 8's ford 10's and 93A prefects.
All we ever changed was the generator and regulator, bulbs and flasher units ( if fitted)
The wiring and the starter motors use to handle the change with seemingly no problem.
I cant see why that would not still apply to modern wiring.
Alternator, regulator, bulbs and any lighting relays.
The starter solenoid , starter motor, should service ok.
Even the old 6 volt windscreen wiper mtrs handled 12v ok.

[Eddieb]

Thanks guys. This is late 60's, no starter motor and the only lights are headlight, taillight, and brake light. There's no idiot lights at all and I'm not even sure about a speedo backlight but there's definately not on on the rev counter.

[Flip]

I use to do 6volt, to 12 volt conversions on VW beetles, Morris 8's ford 10's and 93A prefects.
All we ever changed was the generator and regulator, bulbs and flasher units ( if fitted)
The wiring and the starter motors use to handle the change with seemingly no problem.
I cant see why that would not still apply to modern wiring.
Alternator, regulator, bulbs and any lighting relays.
The starter solenoid , starter motor, should service ok.
Even the old 6 volt windscreen wiper mtrs handled 12v ok.

+1 what he said....

I have done the same conversion to my austin 7.

My 24v landrover has a std 12v starter motor. It spins up rather quickly, never had a problem to date.

[BMWST?]

Thanks guys. This is late 60's, no starter motor and the only lights are headlight, taillight, and brake light. There's no idiot lights at all and I'm not even sure about a speedo backlight but there's definately not on on the rev counter.

no idiot lights! how will you work it?

[F5 Dave]

A higher quality idiot at the controls