I put heatsink compound on a few of the mechanical connections in the flashlight, like where various places screw together. The body of the flashlight still gets pretty warm though, so I guess there's enough heat being drawn away from the LED. I may end up having to clamp the flashlight to the bike with metal clamps, so that the bike can be used as a giant heatsink. More testing is in order, I think, before I take it on the road.