Advice needed on wiring.

[charlski]

Hi all, my knowledge of wiring is to say the lest extremely limited, so i am hoping some one knowledgeable can point me in the correct direction. I am wiring up my P11 with no lights, so basically all i need to wire in is a horn (daytime MOT requirement) and a kill switch to stop it running !! I have been scratching my head how to do this ... i have a paul goff regulator / rectifier and a sparx capacitor.

I have scribbled down the attached diagram, can anyone take a look at it and tell me if im on the right route, and if not what i need to change ... thanks in advance for any help. KC

[charlski]

Can anyone see this file, first time i looked it was huge .. then gone ... ??

[clive]

fit a bulb horn and that's half your MOT requirement met!

[Colin F]

Yes that should work.

Unfortunatly you bought a Goff regulator, that is not one I would recommend for this application.

The best unit for what you are trying to do is the Boyer powerbox, this has a capacitor built in and is recommended for use without a battery (which I don't know if the goff one is).

[SideValve]

I think horns have to be cabable of a costant tone now so have to be electric.
I run mine of 4 x AA batteries :¬)
Personally I'd add a small modern battery into the mix.

[charlski]

Colin F. Thanks for your feedback, didnt realise about the other option or would have gone with it, the Goff rectifier / regulator definetely needs a separate capacitor, does the kill switch wiring look right to you with it earthing to bars ?? going to try and wire it up tomorrow.

Thanks

KC

[Colin F]

Colin F. Thanks for your feedback, didnt realise about the other option or would have gone with it, the Goff rectifier / regulator definetely needs a separate capacitor, does the kill switch wiring look right to you with it earthing to bars ?? going to try and wire it up tomorrow.

Thanks

KC

No the kill switch wire needs to go on the other side of the coil so that it makes a constant feed through the coil rather than the interupted flow caused by the points, this will prevent it from sparking.

If it would work as you had drawn it, the horn would also kill the engine when operated!

Earthing it to the bars is ok. If you decide how ever you want a switch, that will need to go in the feed TO the coils.

[KenF]

Must admit I've not got any hands-on experience with such a circuit, Kevin, but one way of thinking about it is to treat the Sparx capacitor as if it is a battery which goes flat very quickly, but can output a helluva current in the process.

I think the horn circuit will be fine, but the kill-button circuit is fraught with problems. Pressing the kill button will short out the capacitor, trying to get it down to zero volts, so there's going to be a helluva current going through the kill switch. But while the engine's still turning, the poor old regulator is going to be passing as much of the alternator output as it can to try to keep the capacitor voltage up to 13 volts or so. Whether it would actually kill the engine, I dunno, but it would probably kill the regulator or kill switch in short time.

As Colin says, the kill switch needs to go to the other side of the coils, assuming there's a single contact breaker and dead sparks, so that pressing it shorts out the contact breaker. Of course, if you've got two contact breakers for the two coils, then you'd need two kill switches, one for each cylinder. Could be fun. Far better idea, of course, is to fit a magneto!

Cheers,

Ken.

[charlski]

Thanks Ken & Colin ... electrics is another world i dont understand !! i spoke to Paul Goff at Stafford Bike show today and he also says get rid of the kill switch, but wire a ignition switch straight into the live after it comes out of the regulator / rectifier.

So i will give it a go this way

Hopefully will do the trick.

Thanks

KC