Gents,

     I am now at the stage of a fully rebuillt rolling chassis and looking to refit the engine.I have the FEMSA ht coil set up and im keen not to have to remove the flywheel magneto.My problem is that i only have 3 different coloured wires exiting from behind the magneto and the plate and i would like to fit a kill switch on the handlebar.Every wiring diagram i look at (haynes/clymer manuals ) shows four wires required with one for the kill switch.Is there any way to fit a kill switch without the fourth wire?.I would intend to form a waterproof connection  outside the crankcase grommet where my 3 wires at present are cut with fuel pipe waterproofing protection from the grommet as per a previous post in "bultaco today".All/any advice welcome,im fairly competent mechanicallly but electrics confuse me.Thanks in anticipation.Hopefully pictures to follow.Stuart Kerr.

You should have a black wire running to the ht coil, connect the kill switch to this wire and the contact will earth out to the bars , engine will stop. The other colours will be green, that is an earth wire so install a cable lug and ground it by using the ht coil mounting bolts. Next wire should be a yellow , that is the lighting circuit feed.

Hope this helps.

Depending on witch kill switch you have if it's the original style made from metal then it will earth on the bars most others have 2 wires 1 will need eathing the other goes to the black wire. Iv'e just put a new electronic ignition on my newly built 199A Engine all i did to water proof the the wire was fill the rubber gromit with silicon and run the wire on the inside off the down tube.

Edited September 3, 201510 yr by bondy

Gents,

      Thanks for this information,i have ordered an old style kill switch and will hopefully get done this weekend.regards.Stuart Kerr.

Stuart, you really need to vent the mag case to prevent sweating, however I don't know what model

you are working on??

M199 forward have a vent hose.

Would also suggest an automotive condenser under the tank while your at it.

 

Larry

Gents,Bike is a model 80  250cc sherpa homerlite tank,I havent had any time to start rewire yet.hopefully soon.

           Thanks.regards.Stuart Kerr.

When i stripped my bike ready for rebuild i made some photo of the bits i did not understand here are some of how the ignition was set up. If some one has time to to look and see if this is right or good and bad points ...... That would be nice.

 

The bike is a 199A and it runs well, i find photo helped me a lot when i putting it back together hope this helps you