Light Switch - Warning!

[alanp]

A word of warning to think twice about trying to be a clever clogs and use the No. 6 terminal to use as a magneto/engine stop, by connecting the magneto to No. 6 and running an earth wire from the copper clip adjacent, to avoid a separate switch/button for engine stop. This will close No 6 to earth (and hence stop the magneto firing) when the light switch is off and ensures you always ride with your lights on for safety.
If you take a look at the attached photo you will see at the pencil point how close the central rotor comes to terminal No. 6 and also the copper clip itself on some switches,with the headlights on - in fact the quality of these switches is so poor generally that slop in the rotor pivot can easily cause contact between the rotor and No 6/earth especially when running at high speed with the usual vibration. You know why I know this, right?
Alan

[lawnmowerman]

Another example of the poor standard of parts nowadays but none the less, a good safety idea to force driving with lights all the time.
Did you junk it or is it possible to pull it apart and "Dremel" some clearance.
Jim

[bsa-bill]

I have bought a new one of these due to the switch I have not having this bit at the top - as yet have not had time to look into it other than a quick check with a meter to see what connects to what.
Looked at a Goldie wiring diagram but still not too sure what this bit does.
My dilemma was trying to understand how the tail light could be wired without directing current to the headlamp - penny finally dropped (light came on) that tail light does not come on anyway without the headlight.
Also as stated elsewhere the speedo light is not required for MOT so I can take my time to sort the lights out as the main ones are working

[lawnmowerman]

I'm a bit confused here Bill - not difficult after a certain age! 
When you say the tail light should come on with the headlight did you mean headlight pilot or headlamp main and dip (or both).
My tail light comes on with the pilot (first position) and main/dip (second postion). Apologies if I am stating the obvious.
BTW if you have 12v and have not already done so it is worth trying the halogen main beam bulb and to lower the consumption, an LED rear bulb (shines red in the middle for stop and tail and has some white LEDs around the outside for numberplate lighting). I think you can get a headlamp pilot in LED too.
I have been following your project with great interest and looking forward to some pics of the finished article.

Jim

[alanp]

Jim, I wanted to Dremel it but couldn't take metal out of the No.6 terminal without weakening it beyond use and didn't want to Dremel the leading edge of the rotor because I felt that, with the rotor in the side light position, the rotor might tilt over further against the small nylon roller under the copper clip which helps counteract the contact spring force and I didn't want to risk any more rotor tilt as well as risk the pivot arm moving closer to terminal No.6 when the rotor surface is ground back a bit. I didn't try it to confirm this.
The top of the rotor has a machined recess to clear the copper strip but as we know they are not always manufactured as they should be.
I junked it.
Bill, when the switch position is in 'off', the terminal No.6 is connected to the copper clip via the spring loaded pivot arm which swings into contact with the terminal due to the flat on the rotor.
Alan 

[bsa-bill]

Jim  I'm beginning to see the light, I was sort of thrown off track by the fact my switch does not have the rocker assembly or the copper arm from one of the terminals, in fact it just has ordinary terminal there.
Had a look at the new switch between coats of paint on  my Flash today (local vintage show Sunday) and can see how it works
 
Not you that's confused Jim, the confusion gene is alive and well and lives about 5ft 10 inches from my feet

[iansoady]

If you wanted to do this (and I personally am not convinced of the benefits of daytime lights), why not just use a N/C relay energised by the lighting circuit and switching the kill switch lead?

[alanp]

Ian, yep that would work fine. Using the switch's contact facility looked like an elegant solution until I realised what poor quality the switches are.
Alan