So I hired a guy 5 months ago that was moving from Champaign IL after his father passed. When he was moving he had to sell a bunch of his dads things. So I ended up buying this bike for 150.00 bc it looked cool. I told him if I couldn't get it running I would put it in the yard and make a flower bed around it. You know how it goes, complete restoration in progress now that I'm in it. The bike was parked in his garage since 1983. Now that I've nearly finished the restoration. no spark!!! And no info anywhere in the world as to what bike this is. As far as I can tell it's a 1969 yamaha yg5s 80cc 2 stroke 6v or 12v based off the vin lookup. I am unable to get the magneto/flywheel off to clean it up in there. Or to go ahead and put new points and condensor in. I am unable to find the wiring diagram for the bike anywhere. The tail light comes on when I try to kick it, I get anywhere from negative 4 to +122v at the plug boot when kicked. Points gap is cleaned and set to .016 plug is at .30 AND points are open at TDC. I grabbed my sons coil off his pw80 that I know is good and his plug and nothing. I need help.
What bike is this? VIN# G5 -301685
Is it 6v or 12v?
Is there a wiring diagram anywhere in the world for it?
What plug goes in it?
What is the test ohms for the ignition coil?
Voltage at plug boot when kicked?
Voltage at coil wire when kicked?
Does it have to use a battery to spark I wouldn't think so?
I guess anything anyone knows about this bike would help so much. Please I'm about to give up.

My guess is 1969 G5S in Adrian Blue

The experts can weigh in on other answers if I am correct

yamaha-enduros.com/index.php/workshop/wiki/2-1968-yg5t

This may be close?

www.cyclerestorer.com/pages/show_model_s...&manufacturer=Yamaha

Its not electric start. 99.99% sure its 6V, check the bulbs.

That vin lookup is all I have been able to find on this bike. If I search 69 YG5s wiring diagram, source coil, ignition... it brings up yg5t info and some other models that have a electric starter all wiringn is different. I am assuming it is a 6v system anyone know how to test this ignition system?

The front bulb has a 6v on it . Thanks i didn't think to look at them.

I can't use the link says there is an error

Should be a black or black/white wire out of stator. Run it directly to ignition coil to bypass everything as it looks like your wiring is being messed around with.

Plug gap should only be 0.020"

If you have a good ohmmeter, you can check the resistance of the stator and ignition coil... stator should be between 1 to 2 ohms with points open, 0 with points closed.

There aren't any "voltage" tests to do.

Spark can be hard to see in bright light. Best to check in a darkened garage.

These systems are robust... a standard 27 x 1.0 LH puller should remove the flywheel. Motion Pro 08-0026 is a good quality puller at a good price. Cheap knockoffs can ruin the threads.

Yamaha used pretty standard wiring on most early models... colors were standard... and sometimes all they had was a generic diagram.

Here's the generic diagram for the ignition. The area circled in blue is all inside the mag. The red is the black wire to ignition coil. Grounding the black wire is what the key switch does to kill spark.

Also, here's an old Yamaha document showing the VIN is a 1969.







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