electrical query

[Steve]

ok so right or wrong I'm going to attempt to bypass the lighting switch on the headlight, in favour of some switches on the handlebars no real point other than I want to. I shan't ride at night unless I accidentally get caught out. now I've been looking at the wiring diagrams in my book of the AJS now not sure if its that my book is 1932 to 1950 and my bike is 1953. but just as I was hopefully getting to grips with how to wire it I've noticed that the book diagram is negative earth and my bike is positive earth. so I'm not sure how this this effects the power feed?
or am I just confusing myself.
hope this makes sense as I'm a bit iffy with electrics.
So why bother I hear you say Ha well hopefully I might learn something and you have to start somewhere.

[g80csp11]

positive earth is correct for 1953 - owners handbook shows iring diagrame at the back
http://archives.jampot.dk/book/Owners_m ... ingles.pdf

[Steve]

positive earth is correct for 1953 - owners handbook shows iring diagrame at the back
http://archives.jampot.dk/book/Owners_m ... ingles.pdf

So I assume that means that the live feed is going to be different then?

[g80csp11]

just means you are switching the negative ie power lead is negative through switch and bulb to the ground (positive )

[Steve]

just means you are switching the negative ie power lead is negative through switch and bulb to the ground (positive )

Ah right so just like with mains electric where a black or blue becomes a live and you sleave it brown.

[Groily]

just means you are switching the negative ie power lead is negative through switch and bulb to the ground (positive )

Ah right so just like with mains electric where a black or blue becomes a live and you sleave it brown.

Well, you don't need to disguise anything or change the colours of wires, you just swap the wires on the battery.
You'll also need to ensure the dynamo polarity is correct, and that the ammeter needle moves the right way to show charge and discharge with the reversed earth - and if you have an electronic regulator you'll need one that matches the new earth.

Just my ha'pence worth, but I can't think there's any real point in changing from positive earth, correct for the year, unless you're thinking of adding modern gizmos of the sort which require negative earth.

Ref ditching the switch, you'll probably find some of the wires aren't long enough to get to switchgear on the 'bars if you use an original-style wiring loom. A 3-position Lucas switch in decent shape is more robust (nice big terminals with screw-fittings) than many of the 'bar end options, and is also designed for simple connection of your 'power feed' from the voltage regulator to support lights, charge the battery and hook up the ammeter. The old style dip-switch & horn button is the bit that it can be worth upgrading though - they ARE flimsy.

[Reynard24]

Just to amplify Groily’s point about flimsy switches - make sure your chosen switch and any wiring is capable of handling full system current. Many of the pre-wired switches have very thin cables and low quality contacts. If you want to use these you’ll need relays to handle the current and this can complicate the wiring.

[SPRIDDLER]

A 3-position Lucas switch in decent shape is more robust (nice big terminals with screw-fittings) than many of the 'bar end options,

Many of the pre-wired switches have very thin cables and low quality contacts. If you want to use these you’ll need relays to handle the current and this can complicate the wiring.

When I had to convert my bike to have indicators and all the R/H controls on the left of the 'bars I experimented with numerous 'proper' motorcycle switches from eBay sellers. They were all (unsurprisingly) of Chinese make. None of them were weatherproof to any degree whatsoever and caused nothing but trouble, having to use switch cleaner and WD40 every few weeks to get them to function. (Such was the intermittent performance of them that I had a can of switch cleaner with me when it was MOT'd).
I took several failed ones apart and they were cheap and nasty inside - more like a kid's toy, with flimsy corroding contacts hopefully held in place by tiny moulded pimples and feeble springs. It's a wonder that they worked at all even in dry weather.

[Andy51]

I agree with Spridler, Reynard and Groily. Most currently available new switches are very poor quality and if pre-wired, use far too thin wires (and in the wrong colours). In the past I have been able to replace the leads, but having fitted a modern all-in-one switch that would not take thicker leads, I had to fit relays for headlight and horn. Not a problem, and they cost under a tenner, but it does lead to a crowded headlamp shell! Stick withh the Lucas main switch - darkness comes slowly and you will have plenty of time to use it safely. Andy

[Steve]

Oh well I like a challenge plus what's the worst that can happen burn out a few wires and revert back to original condition.
I'll post my progress.
If nothing else it should provide a few laughs for you all.