electrics

[pugslee]

Hi Guys

Can anybody help

Can anyone measure the voltage that comes out of the lighting coil on a sherpa 350 199 model.

I am trying to fit lights and horn for mot and only get 2.4v on the red wire for horn,(6v horn fitted and does not make a noise when wired direct to earth or through switch). tested on a 6v battery and works fine. It is a new ign coil from bultaco uk. The yellow wire gives out 3.2v and is giving me a good brake light when pressed and not bad front and back light. but if i press the brake pedal with the lights on all goes very dim almost like a bad earth problem. all earths cleaned. i have disconected wires from magneto and replaced with a six volt torch battery to test and all works well.

any help very much appreciated.

[nigel dabster]

Hi Guys

Can anybody help

Can anyone measure the voltage that comes out of the lighting coil on a sherpa 350 199 model.

I am trying to fit lights and horn for mot and only get 2.4v on the red wire for horn,(6v horn fitted and does not make a noise when wired direct to earth or through switch). tested on a 6v battery and works fine. It is a new ign coil from bultaco uk. The yellow wire gives out 3.2v and is giving me a good brake light when pressed and not bad front and back light. but if i press the brake pedal with the lights on all goes very dim almost like a bad earth problem. all earths cleaned. i have disconected wires from magneto and replaced with a six volt torch battery to test and all works well.

any help very much appreciated.

don't need lights for mot.

[b40rt]

Day time MOT does not require lights, but if fitted must work.

Constant tone horn can be bought from a cycle shop.

Try and find an MOT station that knows a bit about off road bikes.

[pugslee]

don't need lights for mot.

Hi

i realise i dont kneed the lights for mot and yes i could fit a battery horn.

I have seen pictures of bultacos and videos on youtube with lights and horns so it must be possible. i would just like them on( and working)

Cheers

[feetupfun]

The voltage on a basic system like that will depend on the RPM of the motor. What RPM are you measuring the voltage at?

[cunpr]

There's a wealth of data on these older systems if you search for Femsa or Motoplat;

http://www.motelek.net/motoplat/licht/alu_6v19_20_5w.png

unfortunately you'll have to translate from the german.

On my other PC I have some already searched stuff but here's a starter.

Regards

Paul C

[pugslee]

Hi

I tried it at tickover then about half revs but still no horn or lights with brake light.

Thanks

[feetupfun]

My memory of running lights on my Bultaco in the mid 1970s is that the 6V headlight bulb glowed dull red at idle, bright red at mid RPM and pale yellow at maximum RPM. If you brought the brake light on, the headlight went much dimmer.

I'm sure that you can get your lights to work very well with modern technology. There is a place in South Australia that specialises in setting up all sorts of dirt bikes for racing right through the night and they have been doing it since I was a kid in the 1970s. I would not expect that the standard lighting on your Bultaco will work much better than what you have found already.