73 850 kill switch wiring??

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Nov 5, 2006
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Hey all
i replaced my stock wiring switchs with an all in one job since the screws were frozen on the old bits and they were trashed - now i have all the trunsignals/lights/ etc.. working but the thing won't start (i sometimes wonder why i do these "upgrades" rather than leaving good enough alone!)- i hooked up a timing light and see that i'm getting no spark to the cylinders so i'm thinking the kill switch wiring must have to be connected to get a hot connection going the the coils/distrubitor etc.. any ideas what wires these are on the old cluster (think its the righthand one??) and where they run that as the wiring diagram is a little hard to deciper (for me at least) as to which were for the interupt button
any help would be great - and make my thnankgiving really thankful!
mike :?
The old kill switch would make a connection between the white wire circuit and white/yellow. According to the wiring diagram that white/yellow wire changes to white/blue at the multi-pin connector that feeds the ballast resistor and coils. So hopefully there should be two wires in your new switch unit you can identify that can be connected to the original white and yellow/white wires?

Some kill switches 'kill' by grounding the ignition circuit (some electronic ignitions) so that type of switch won't work.
thx L.A.B
as soon as there is enough light i shall try your suggestion white to yellow /white!

I let you know if that does it
thx again
L.A.B. is correct (as usual) the kill switch on the old cluster interrupts the feed wires from ignition to coils. It's a poor design because even when it's working there can be a high resistance through the wires reducing some of the current to the ignition. On mine I connect the ignition feed through a relay and use the kill switch (Japanese type) merely to operate the relay.
hey guys
crap the white to yellow/shite wire still didn't work - your guys know what/of i can ust run a hot wire to coil(?) and try kicking it over to make sure its not a coil/boyer failure??
That's strange, if it was working OK beforehand with the old switch?.
Try running a jumper wire from any white wire connection (hopefully live when Ign. is ON?) to the Boyer white wire (if it is still a Pos. ground system).

As I now understand you have a Boyer ignition fitted, please disregard what I said concerning the ballast resistor as it isn't used with the Boyer kit.
Hey L.A.B
yeah she worked fine - but that being said it has been a while between running it w/ old switches and new one as I had the tank etc. painted so while they were out i put on the new gear - rewired a month ago and never had a chance to try kicking it till few days ago -
thx for assistance - sounds good i shall try a white to the boyer (still is a positive ground) and see waz up - i took off all the new switch wiring to retrace and make sure there are no screw up but shes not blowing fuses so have to see
i image its one damn wire!

maybe the prblem is a damn texan also
ok thx again!
mike :lol: :lol:
thx again L.A.B - sure enough ran a hotwire from handlebar switch straight to bower and got a nice spark - bike ran like crap (well it had been a month) but at least she started now tune up time!
I think that the most valuable item you can carry on a Commando is a length of wire with suitable connectors to run from the battery to the ignition unit / coils.

It saves hours of guess-work and lets you sort out problems in the comfort of your own garage.
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