Winding 6V to 12V on XT 500?

[Paul]

Hello!
I do not know if it's the right place, but I do not know too much or ask my question ...

So I have a 500 xt 1980, it is great, except a trick: it is in 6V, and its illuminates that slab.

So I would like to rewind the lighting coil, (separated from the ignition as on a mob) to get out of 12 V.
I would therefore like to know the "formulas" for having 12 V, by rewinding. (how to calculate the length, the diameter, of the wire, compared to the one I have for 6V)
Knowing that I would like to recharge a baterie, and have enough power for a H4 headlight in 65 W.

Thank you!

Pablo

[chatelot16]

to double the voltage just double the number of turns

for the diameter of wire it is necessary to put the biggest possible: it is in general possible to put bigger than original to make more power

but the power is limited by the size of the iron core of the coil, and the magnet size of the magnetic flywheel

this lighting system in alternative moped style is really bad: I prefer to straighten everything send to the battery and put the lighthouse on the batterrie: at least the lighthouse does not go off when we stop

Another solution, led headlamp: the efficiency of the LEDs is so much better than the lamps, that with the weakest coil 6v we can have lighting as powerful as we want, and more reliable than a lamp

[Christophe]

The simplest and least expensive solution would most certainly be to put a converter (if DC) / transformer (if AC) 6V to 12V rather than rewind the alternator ...

[chatelot16]

put a converter to turn the 6 into 12 will make a power loss in addition

Rewind allows you to choose a diameter of wire that better fill the coil, so increase the available power

modify the wiring to put the headlight on the battery also allows to have more power: even if the headlight consumes more than the coil produces slow motion, the battery will be charged when the engine runs faster

other note: in general the coil has one end to ground, and the other end to the regulator that charges the battery: it is therefore a simple rectification alternation

when I remake a coil, I leave 2 wire for the 2 end of the coil, it allows to do a double alternation rectification, and it almost doubles the power available

[Christophe]

Ah OK! I thought we were starting from a problem of tension, not lack of power ...

[dirk pitt]

going from 6V to 12V has no influence on whether it lights up better or worse.
it is only the power and technology of the bulb that is important, not the voltage.
we can have bulbs of 12V that light little and 6V bulbs that light up well.
certainly nowadays, it is easier to find 12V bulbs than 6V.

[Paul]

this lighting system in alternative moped style is really bad: I prefer to straighten everything send to the battery and put the lighthouse on the batterrie: at least the lighthouse does not go off when we stop

Indeed, it's good for her that I want to rewind, to have enough power to recharge a battery.

when I remake a coil, I leave 2 wire for the 2 end of the coil, it allows to do a double alternation rectification, and it almost doubles the power available

That's what I plan to do, with deudeuche alternator diodes ... it should work ...

I will rewind with a wire twice as long, and a little thicker (in diameter) than half of the current one.

The thank you box

[chatelot16]

so that the thread occupies the same place with 2 times more turn it does not need 2 times less in diameter, but 2 times less in section in mm2, therefore 1,41 times less in diameter

[Former Oceano]

The rectifier and voltage regulator is often separate and located under the tank.
For 12V passage of the lighthouse, there may be a problem with the base of the bulb. It will surely find a round 12V headlight with a close diameter.

Then it is necessary, as the current coming from the coil is alternating, a U <> 2U transformer with a whistling power will be appropriate.

Switching to 12V allows the use of a halogen bulb that will have a better light output.

Otherwise there are Xenon motorcycle kits. I have a bi-xenon kit on my GS500E. The lamp makes 35W and illuminates better than the old halogen H4 of 55W.

The difference between Xenon and Bi-Xenon is as follows:
bi-xenon = code (passing light) + lighthouse (high beam) in xenon
xenon = halogen code + xenon lighthouse

If not pamper your XT500 is a mythical machine that climbs trees ...

[dedeleco]

Totally agree with Chatelot16 to listen thoroughly, and therefore with LEDs well fed unnecessary to rewind.
Measure before the actual power of this alternator ??
It will not change, if too weak, with a wire 1,4 times smaller in diameter, because the power is proportional to the weight of copper put.