Been working on the rear light over the last few days...why couldn't Ariel have stuck with the normal MT110...it would have been so much easier
. But they didn't, and for '39 only, we have the motorcycle version of the MT1130 and a centrally mounted lamp. I didn't even bother trying to find an original lamp since they were only used by Ariel and only in 1939, so have done what most '39 owners do and have adapted the car version that was fitted to MG wings etc, the MT1130. The main different is that the car version doesn't have a slot for number plate illumination. Surprisingly, Drags sell the rubber boot that the lamp sits in.
In the photos above, I've already cut the slot in the alloy casing of the lamp and have made a U clamp + bolt & nut to hold it to the plate and rubber boot. The lamp will be painted black.
Took some time on choosing the light source. With modern LEDs, you really do have a huge choice now but eventually settled on a light board rather than an LED based bulb that plugs into conventional bulb socket. This board was the perfect diameter to fit in the alloy lamp case and has two LEDs at right angles for the number plate.
The board comes with a mounting kit for fitting into an MT110, but that was of little use in my application, so I had to make up a brass backing plate that could be secured into the MT1130:
And a quick test of the light. My digital camera hasn't coped too well with the actual LED colour; here it looks orange but in fact, it's a very good deep red. First photo is the lighting circuit, with the 2 number plate LEDs, and a test piece of printed paper. The second photo is the braking circuit which is much brighter, although not in the photos.
Very pleased with the performance of the LED light board and, of course, its very low current drain.. The board works out at approx £25 (incl. postage and VAT), so it is more expensive that a bayonet LED bulb. I had planned on using a red glass stain on the lamp glass, but it really isn't necessary with these red LEDs on the board.