Miller Dynamo and a LED?

The problem is that the rear bulb is only rated 0.6w, and it's a 3w dynamo! It's designed to use a 2.4w front bulb and a 0.6w rear, so by either a)attaching a front 2.4w light, or b)using a 3w rear bulb, it should stop blowing (and if you attach a 3w rear bulb it'll be a hell of a lot brighter too).

But anyway, if you wanna go for LEDs, I've been thinking about it lately too:

There's a few ways of doing it, depending on how much work you wanna put into it. FYI there's no negative wire, they just use the frame as the ground.

Simply plugging a 3w LED into it will work, but because bicycle dynamos (unlike true dynamos) put out AC instead of DC (as in, alternating current, the current goes positive-negative then negative-positive), the LED will flicker very annoyingly at low speeds (because LEDs, like all diodes, only allow current to pass in one direction). A couple of big 3000uF capacitors (found in an old computer motherboard, for example) wired in series should smooth out the worst of the flickering and provide illumination for a minute or so after stopping.

Because these old dynamos are unregulated, the voltage can climb massively if you're going down a hill quickly, so a Zener diode or resistor is a good idea, to keep things under 6 volts.



A better way of doing it would be to wire in a bridge rectifier (which converts the AC current into DC, so the LED won't flicker at all), smoothed by a 100uF capacitor in parallel. The problem with this is that it'll need to have a proper negative wire, so it'll have to be isolated from the frame (I was thining about making a plastic mount rather than a metal one).