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.
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.
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.
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.
Kim I refer you to my previous post, where I posted a link from the technical section of this site. All the cables are the same black colour with coloured ID tags on their ends. Ron
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.
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 ?
I just experimented with an LED tail lamp. But it doesn't accept any resistance so is on maximum light up as soon as I turn the tail lamp on. So I've gone back to my 21W bulb, which doesn't appear to draw much current according to the ammeter? Ron
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.
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.
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
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:
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.