Hi all,

First a little background info. I am trying to use a Shimano dyno hub on the front of my '68 Raleigh DL-1. For that "vintage" look I am using a SA headlight. I purchased a LED bulb and I had the bulb that came with the light.

In stock configuration I found that the LED was very bright for almost 1/10 of a mile then it died. Having read somewhere that since the Shimano hub grounds through the steel of the frame as well as the wiring might put something out of phase, I reversed the polarity of the wires (swapped left for right) which gave me LED light for an additional 1/20 of a mile then nothing.

This lead me to use the original bulb that came in the headlight, this provided light output close to the output of the sun for almost 1/20 of a mile and it burned out.

Now, I have read and researched about the LED bulbs and it seems that everyone draws pictures (schematics) of a rectifier, then a rectifier with a capacitor, then a bigger rectifier with more capacitors and some resistors to run 6 LED's. I just want one to work, I am NOT trying to see just be seen. A little more research finds that all of the soldering and purchasing of diodes can be bypassed for $2 purchasing a rectifier at Radio Shack. BUT....

What specs for the rectifier from Radio Shack?

Also, adding a capacitor seems great right up to the point where there is the mention of a serious shock potential if the light bulb/LED fails so I found mention of adding a resistor to bleed off power but no idea of value or how to hook it up..

And... after doing some quick testing I found that the metal headlight grounds very well through the bicycle frame. It's easy enough to isolate if needed. I also found that the SA headlight switch did not cut power to the lamp, it cut ground. So I moved the wires around so that power is now disconnected when the switch is in the off position.

Lastly, am I barking up the wrong tree? I have the dyno hub and the headlight and would like to use them. Is there something that I'm missing?

Long post but I want to get all the information that I have out there.

Thanks in advance,
Lester

PS Do not refer me to a particular website that proclaims all knowledge of bicycle lighting. I have been there and call BS. I have dealt with similar folks in other lines of endeavor and they stand out as salesmen more than technical advisors.