Britbike forum Forums British Motorcycle specific Brands Triumph bulletin board 1955 6T Oddities

Along with my bike being a rigid frame from the factory, I have noticed a few other differences. It has an AMAL carburettor not an SU (see photo). It has a hole in the downtube frame behind the carby for the rubber to the 'D' shaped air cleaner. It doesn't have coils only the magneto (see photo) but with 4 high tensile cables coming out of it, 2 for the plugs, 1 for the wiring harness & 1 for a kill switch that my Dad fitted. When I put it all back together what do I do with this extra wire?

Show us the wires.

The wire to the harness will be the original ground wire. It's probably broken which is why dad fitted a new one. You ground the magnet to stop the engine, but I guess you knew that. I'd go here and read up on the tech if I were you: http://www.classicbike.biz/Triumph/Repair/45-55/45-55TriumphRepair.pdf
Asking good questions is easier if you have some knowledge. Sorry, don't mean to be condescending or anything, just trying to help.

SR

Thank you for the link. I have a Haynes manual & I bought Roy Bacon's book but they deal in generalities. Because my bike was built in 1955 but a rigid frame & also for the police with sidecar spec it seems to have a few differences from the norm. The ignition switch has a key so I thought that Dad had put the cut out switch as a deterrent.

To correct my original post, there are only 3 wires coming from the magneto. The other wire comes from the back of the primary case. My query was relating to the kill switch that my Dad had fitted as on the lighting switch on the top of the nacelle has a hole for a key. I thought that was how you turned it off.

the magneto end cap is connected to the points low tension side by a carbon brush .
a magneto key switch , up in the headlight nacelle
connects by a wire to the end cap , ...
the key switch can ground ( earth )
the magnetos primary coil induction ... ( low tension through the points )
and when off , with no primary AC ... there is no secondary output from the high tension side .
( alternatively , a mageto kill is often just another horn button , and the kill lasts as long as the button in pressed )

wiring would be similar to concept in image below .


.

I have just found out via an old friend of my father's that he changed to a magneto in the late 70's. I think he was more used to it. Should I keep it like that or put it back to original as I rebuild it?

If the mag is good I’d leave as is.

It’s a family bike and part of its story.

That is entirely up to you !

There are some that say that a magneto will ALWAYS get you home.
But it has to be in GOOD condition.
The manuals of old refer to the yearly servicing of same, by your local Lucas depot.
These days, some magnetos may not have had a service for decades ...

And some say that points and coil will always get you home.
Your generator/alternator and probably your battery (and wiring) has to be GOOD though.

Notice anything in common here.
Keeping electrical stuff in GOOD CONDITION is the key ingredient here ?!
Hopethishelps.