I am working on the directional flashers for a 1971 HT1 90cc Yamaha. It has a 6 volt, two prong flasher unit under the tank. I removed the ‘can’ off the flasher unit expecting to find Thermo-electric bi-metal switching arrangement. However, what I find is a set of points setting atop a magnetic pole shaft which is wound with a coil of very fine wire and then wound over that is a coil with very heavy wire. (A heavy wire coil wound directly onto the a very small wire coil; covering it completely.)

It looks like some kind of ‘buzzer’ arrangement to me. There is one lead that terminates in the upper portion of the can thru a sealed partition, which I did not tear into.

I got it to work ok by repairing a bad solder joint. And while holding it off the bike I got a nice little jolt of electricity when the directional light switch was activated while I was touching the bike’s handlebar.

I am interested in knowing how it is able to flash the directional lights.
Anyone know how it works or maybe can supply a circuit diagram of what is inside this type flasher can.?

Not an electrical guy but does it seem similar to the mechanical one in the first drawing.
www.arrow.com/en/research-and-events/art...tromechanical-relays

No. That is a standard SPDT relay.
The flasher can had one coil on top of the other. Both around the same pole piece, with a contact flapper on the top, like a buzzer.

I think you would have found a capacitor inside... I'm not an electronics guy but my basic understanding of that type is the coils and capacitor work together to delay charging the resulting electromagnet from operating the contact points.

It's been a long time since I had one apart... I can't remember if the points are spring loaded open and when the electromagnet charges up the points close so the circuit discharges and so the points open or the other way around with points closed and electromagnet opening them.

I found my answer at:
www.patu.ca/xt500%20electrical.htm
Scroll all the way down to the end of the article; in the paragraph titled Signal Lights.
Now I see why I was being zapped!

Lots of other good info on this site!

www.patu.ca/index.htm

Thank you for digging in to this. Wanted to repair my relay from 75 DT but also didn’t know the function since this is NOT a thermal relay. Now I know the cap is potted in place since it is not visible and the lead from resistor terminates at potting, making it very difficult to service. At least now I know and will work on a solution for removing the potting material, old capacitor material and attempt to add a replacement cap.

Did anyone find a way to fix the original 1971 flasher? My turn signal lights will light, but they don't flash. When I go left to right I can feel a click in the flasher relay, and I took it apart and it actually looks very clean. I'm assuming the potted capacitor at the bottom may have gone bad, and I was wondering if I could just put another capacitor in there. I ran some fine grit sandpaper across the contacts to clean them, and put it back in but it still won't blink. I know from working on guitar amplifiers that capacitors don't last 50 years, so that's probably the issue. If I knew the value I needed, I might be able to stuff one in there.

 

I got a couple to work by widening the points gap - just bend the arm a smidge.

So there's supposed to be a gap between the points? As I took it out they're just touching at rest.

 

Have you checked the wattage of the lightbulbs fitted?