Yamaha qt50 no spark

So when I moved into this house, there was this crusty bike in the back shed that the landlord said was left behind like 5 tenants ago. The registration sticker on the plate expired in 87 lol I saw it as a diamond in the rough.

I spent the summer cleaning and rebuilding her but now on start up I'm seeing zero spark. I think I figured it out but jus looking for some info.

The battery is showing 6.4v, and then the hot wire splits off.. one goes into a harness through the frame so who knows where that goes off to lol, but the other ties into a little black matchbox sized thing with polarity and a diode symbol. Not sure what it's called, but seems important.. When I go from pos. Of the box To the frame I see 6.4v, but when i go neg. To frame i see .8v.. so i wanna say my issue is this voltage restriction right there. When I ohm it out my meter shows OL which doesnt make sense cause I saw .8v with power on it but maybe diodes are tricky..

So basically I just want affirmation that having .8v through the diode is a problem..or is that what it's supposed to do. I dont know where the other wire is going but it should be carrying 6v to a coil or something down by the spark plug.


Re: Yamaha qt50 no spark

Edit: sorry I cant find a way to delete this post, but I added a second post with another little nugget of info!

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