I need a new wiring harness for my 1944 M20 project. It has the amp meter in the headlight panel. Any suggestions on a good place to purchase the harness would be appreciated.

Many Thanks,

Kenny
Oklahoma

email (option): knbright68@gmail.com

It's such a simple harness, and the modern replicas are so inaccurate and ill-fitting that it's best to talk things through here and then make your own. There is no jig more accurate than the actual motorcycle.

Will you be fitting a rear brake light and dip switch or going for 1944 accuracy ?

double ditto on what Ric said
Never seen a decient wiring loom for any BSA for the past 30 years
Dead easy to make your own.
If you are not trying to do an authentic rebuild then consider upgrading by using more modern plugs & connectors .

And to add to what Rik said, it's not really about making a harness, it's simply just laying each wire on the frame and connecting it up at each end. There are only 3 wires running along the tank tube which can be taped to the tube with a short piece of trunking from under the tank to the headlamp (I use a piece of inner tube from a racing type bicycle). The only fiddly bit is the connections at the switch, and that applies what ever loom you use.

More info here. http://www.wdbsa.nl/wd-wiring.htm And since this was written it is possible to buy a good rubber covered cable now. It's all I ever use.

Ron

email (option): ronpier@talk21.com

....& remember, when it come to wiring looms motorcycles are like the ladies, they never complain about having a few extra inches!😉

The biggest problem with making your own wiring harness is getting the correct colours with correct tracing colours. Most accessory shops only sell plain colours and even that is restricted to only the obvious red, white black and yellow.

email (option): tknalder@iinet.net.au

www.rdae.nl 😄

John 👍

email (option): john.kater@chello.nl

email (option): ronpier@talk21.com

See this site for a package of all the colours you need for a M20 in various sizes and really cheap. 1 package is enough to do at least 2 M20's.

https://www.martoparts.nl/pakket-krimpkous

Regards,
Bastiaan

email (option): wdmotorcycles@gmail.com

Make your own so much easyer, I followed Rons advice to the T and his surpplyer with the rubber colour codes also. Only thing I did diffrant was ad a resister to the main feed to the rear light so I could add a rear brake switch and stoll keep an Orginal looking light on the back.

email (option): chriscool@sky.com

These are the 1 ohm resistors I use. I wire the tail lamp and the stop lamp through a single filament 21W bulb. Ron
https://www.ebay.co.uk/itm/122180980450?ssPageName=STRK%3AMEBIDX%3AIT&var=422422868355&_trksid=p2060353.m1438.l2649

email (option): ronpier@talk21.com

www.motolab.nl

John 👍

email (option): john.kater@chello.nl

John, just had a look on that Motolab website, and that wiring loom is absolute rubbish!!! can't be more incorrect!

Stay away from that please guys!

Cheers,

Lex

email (option): welbike@welb**e.net

Ron, are you not working your dynamo ever so hard by effectively drawing 21w at all times ? Surely much kinder to use an LED rear ?

It's only 21W when I brake isn't it Rik? Ron

email (option): ronpier@talk21.com

email (option): john.kater@chello.nl

email (option): ronpier@talk21.com

That resistor won't work with an LED, Ron...I've been trying to double-check about the load on the dynamo using the resistor...Apparently it's not all that straightforward to calculate as the resistance of the incadescent bulb will vary according to current. It would certainly free up some power for the headlamp if an LED was used at the rear. Your resistor will reduce current draw compared with running the 21w bulb, but it seems difficult to find out how much less.

This is the little ceramic 3w resistor that I use with one of Henk's LED bulbs. The set-up only draws milliamps.

I'll use what I've got until you come up with the ultimate solution Rik. The original lamps look so much better with just one wire. Ron

email (option): ronpier@talk21.com

Ron, I quite agree....it would be sacrilege to butcher an original MT110. I can sort of shut out the switch from my mind's eye, but the MT has to have the single screw connector.

Hi With an avionics guy made my own wiring harness, added to my maintenance manual a copy of the wiring harness we made

email (option): Gawls62 @icloud.com.au

I've made several correct color and tracers from disused MG harnesses!
FREE wire, and modern bullet connectors. Bit of harness tape and Viola!

You can wire a dozen bikes from one harness you can get for peanuts.

Start thinking and stop spending. There are loads of free resources
out there. Think recycling (lol)

email (option): britool51@hotmail.com

Hi all,

I have read somewhere that LED lights are going to be illegal on classic vechicles, not too sure if bikes are included.

Dave

email (option): jeepfinger@blueyonder.co.uk

The changes to the lighting regulations have already been made....The available information is both confusing and subject to opinion it seems....Also there's the question of whether what can pass an MOT test is then road legal...and of course, most classics don't need an MOT....:laughing: ...
Life would be so much simpler without the people who have to justify their employment by solving non existent problems by the application of new rules...Ian

email (option): ian@wright52.plus.com

Post-war MG Harnesses are no good for making authentic wartime motorcycle harnesses. We need black cable with small coloured rings;..No post-war bullet connectors either.

In terms of legality, my understanding is that LEDs have never really been 'legal' as the statutes stipulate minimum bulb wattages...but the LEDs are brighter, so it's a nonsense.

What the hell, we're motorcyclists and most of us have spent the best part of half a century breaking one law or another. :relaxed:

'Always break at least one rule a day'...One of my favourite sayings...Ian

email (option): ian@wright52.plus.com

Is there a detachable connection in the genuine loom to enable the rear lower mudguard to be removed? If so, where & what is it?

Yes Bob! It's a single screw together bullet connector. There are, or have been repros around. Ron

email (option): ronpier@talk21.com

Thanks Ron.
I currently use a couple of rubber shrouded push in connectors (tail & brake lights & run on the left side to accommodate the stop switch).
It gives a reasonable '40s-'50s effect but it's always good to know how things were really set up.