I aim having difficulty with the wiring of a lanyard kill switch for a 74 Sherpa T 250. The bike has previously had a multipurpose switch but this has disintegrated. I have eliminated the leads to the lights leaving three leads. I still have a spark with any combination of these leads. Any advice would be much appreciated.

 

To stop the motor, the kill switch creates a short circuit from the low voltage ignition wire to the bike's earth.

The low voltage ignition wire runs from the flywheel stator low voltage ignition coil/points to the low voltage connection on the HT coil. The HT coil is usually hidden by the fuel tank. On the Bultacos I have worked on, the low voltage ignition wire is coloured black.

Bultacos like yours originally came with a connector strip for the wiring on the frame under the front left of the fuel tank. If that is still there, one wire from your kill switch may be connected to the ignition wire using that connector strip. The other wire from your kill switch can be connected to the frame where the HT coil attaches to the frame.

If you are still in doubt, post a photo so others can see what you are dealing with

May, I suggest you use a Lanyard Switch. I think it´s an essential safety device.

Be aware that Apico and Jitsie have reverse  polarity of the magnets. So you can not exchange without problem

16 hours ago, carl ekblom said:

May, I suggest you use a Lanyard Switch. I think it´s an essential safety device.

Be aware that Apico and Jitsie have reverse  polarity of the magnets. So you can not exchange without problem

carl, a lanyard kill switch is exactly what ken is trying to fit to his Sherpa.

 Carl was spot on. You need a Lanyard type tether, not the crap magnet switch. We are the only moto sports that use the magnet for a reason. 

But I must say, in more then 10 years I never had any problem with the magnet. Thought it would be but not so far. Only with the strap. Keep one spare magnet somewhere at the bike in case it disappear . No problem at a steel framed Bultaco.