anyone have some insight into the proper way to ground a tailight to an already working headlight setup that is a single wire frame grounded circuit?

im pretty sure i set it up right but when i set the wheel in motion the tailight burns brightly and the headlight is very dim. however they both work perfectly when not hooked up together.

i have the tailight hooked to the seat, the headlight on the front mount grounded to the frame, and the wires from both light connect to the generator together.

Peter White has some good info about do's and don't's when using a common ground -- let me see if I can find it.

Okay, it's in here partway down, under "Polarity": https://www.peterwhitecycles.com/b&m-hl.php

What kind of lights and bulbs? It sounds like you have incandescent bulbs of too high a total wattage for the generator to keep up, at least at the speed you can spin the wheel by hand. FWIW, LED lights are the cat's meow.

If the tail light draws 2 watts and the head light draws 1 watt, the tail light will burn brighter than the headlight.

The head light should have the higher wattage bulb.

Have you tried switching the bulbs? The bulb's brightness depends on its rating, so in general you'll want the brighter bulb in front.

thanks guys, that seemed to have done it, im not sure what i had on the front for a bulb but it was bigger and had a frosted pattern, i assumed it was of higher wattage. i decided to try my spare tailight bulb in it based on your suggestions and both lights burned brightly befor burning out when the system flickered.

i will have to properly mount the tailight and try a matched pair again and hope the ground stays solid.

this is an original headlight that was on my 73 schwinn from when the bike was new and a tailight i took off of a 77 concord along with some other parts to better the schwinn. What kind of bulbs do you recommend for such a system? not looking to convert to LED want to keep it as close to period as i can.

Typical : 3w available ... tail light 0.6w, headlight 2.4w.

great , thanks. i wasent sure how much i had to work with.

Great thread as I slowly get into a '59 dyno-powered lighting system.
I'm still inclined to get the regulator and go with white LED bulbs.

I have decided to also use a clip-on LED taillight. I prefer seeing up front, being seen from the rear.

ya a battery one for a backup and maybe an extra bulb or 2 sure isint a bad idea. im thinking about getting a full dynamo setup for my mountain bike as batterys just never last long enough especially in the colder weather that is approaching.
for my old bikes i prefer to keep them period correct if i can, i know a schwinn varsity is frowned upon in the bike world but theres something special about the one i have. it looks rather nice draped in chrome period correct fenders and the fact it has the same speedometer and headlamp that were put on it when it was purchassed new in 1973. its in the same condition now as when i bought it off its original owner and is in overall amazing condition. its been garage kept, and routinely maintained through the years. the only real rust anywhere on the bike is the headlamp, the low quality chrome that came on it is rusting and flaking in places.

the bike still had all its original bike insurance, aaa , and saftey course and inpection clip in wheel decoration that it has picked up over the years.

and well the fact its by far the heavyest bike i have ever tryed to pick up, it is a varsity afterall haha. think it weighs in at around 46 pounds it was heavier then a tandem beach cruiser whos owners thought it was the heaviest bike ever made . now that i have added the fenders and leather springback seat .

not the best bike but it has an undeniable character.

Yeah, I'd take the clip-on LED off after rides so the bike doesn't pout.

ok i have an update, i now have 3w of total bulb as fietsbob suggested and the systems works great, for about a minute and then starts to pulsate and flash.

any idea whats going on? i have the tail lights mounted to the brake caliper bolt


* edit * It was a blink bulb -.- with a 1 wire setup it seemed to cut the circuit with every blink and make the headlight pulse aswell.