The copper housings for these motorcycle headlights are going to be built nearly the same as the bicycle lights I detailed previously
. The difference is that the housing for the motorcycle lights will be made with 1-1/4" fittings rather than 3/4" fittings. Also, the coupling is used full length to give the housing enough room to hold the BuckBlock and the pipe cap to hold the LED is cut taller and includes an internal section of 1-1/4" pipe to increase the thermal mass and make a better fit for the 26.5mm lens and holder. Also, the mounting style is different and uses a threaded rod rather than a bent wire cleat.
Holes for the wires to the LEDs also need to be drilled at 7/64" or so, holes for the threaded rods need to be drilled at 5/16" or so, holes for the wire between the headlights need to be drilled at 7/64" or so, and a hole in the end cap of the headlight that will house the BuckBlock needs to be drilled for cable gland at 1/2" or so. See pictures for more clarification.
The threaded rod is bent to allow soldering to the inside of the housing and to give the lights the correct aim when installed on the bike. You'll need to take some measurements of the bike and come up with the proper angle. Depending on the bike, you may opt for a different mounting scheme altogether. We considered using clamps around the fork tubes but eventually stuck with the stock headlight mounting holes. Bending the threaded rod will require the use of a vise to hold the rod while you carefully bend to the appropriate angle. Once bent, cut to length and dress any threads damaged during bending and cutting. To help the bronze rod stick to the solder, grind the threads that will touch the housing flat to clean any patina and to increase surface area. You will have to file out the hole in the copper housing to allow the threaded rod to sit properly as well.