Heres my latest dyno light. Almost 500lm off the dyno.

This is the easiest build yet.

Martins circuit 10 again because it works so well. Circuit in a small box under the stem.

I used inch square section, walls around 2mm thick. Perfect fit for the 20mm XP-E triple, 16 degree loaded with R2s.
I tested a section on the bench with a few leds running at 5W to test heat dissipation, fine with a small fan running. Also noted the bar heats up evenly so 2mm seems to be thick enough to spread the heat around.
Bored a big hole towards one end to let the light out. Chopped a small grove in the other end for cable relief and a matching groove in one of the plastic ends.
Bracket is a flex-tight from cateye, only modification needed was a longer screw (screw head inside the light).
I put the C1 capacitor inside the light head but you could leave it remote. This gives extra cooling area as the light is longer and gives me the option of flipping the light up if using a handlebar bag.
To seal the light I used mylar OHP sheets siliconed to the housing front. To get a perfect fit I taped the sheet to some section and sat in boiling water so it took the shape of the bar. It hazed somewhat but I polished this off. The end caps are sealed with silicone too.
You could run a couple of the triples in the housing but you might want to put some cooling fins on the sides.



A buckpuck is a perfect fit in there too if you're into that sort of thing.


Normal setup, note it hangs below the cable so no annoying shadows.