QA50 - Mini Bike, cause it fell into my lap!


Coast to Coast
So there I was. Riding my fresh c100 around the hood, minding my own business. Making the reasonable amount of noise a 50cc Honda Cub can make.... When out of no where my 86 YO neighbor comes running out of his house waving his arms at me. My first thought was "Give me a break, it's not that loud and I'm barely breaking 32 in a 25." I stop, cut if off and ask Mickey (yep his name is Mickey and he wears a members only jacket) "How ya doing?" he's fine. He asks me If I'm into old scooters. Yes. Next thing you know, he sells me a 1973 QA50.

And here we are:


It's in REALLY good shape and it all seams to be there. I'll take some more pics tomorrow, but this one is a restoration candidate while I gather parts for the 77 CB750.
nice! That is awesome. and so soon after our last discussion. Love it!
yeah, I'm super stoked about this. Pics to come tonight after work. It's in great condition because of a kid trying to "fix" the bike unsuccessfully. I could tell more, but the pictures are so much better.
In the quest to find the factory manual online for free I ran across someone who made this into a "cafe" bike...


Not going this direction, but it's kinda cool.
Pics from tonight. Gives you an indication of size. This thing is tiny!


Now for the reason it doesn't run. The PO's son (about 55) tried to do a tune up a few years ago so his kids could ride it. He thought is just needed a spark plug. It really needed a carb clean/rebuild. But tell me if you see something wrong here....

I'm rebuilding the carb now....
Why is there a spark plug threaded into a spark plug? Stripped head and this is some bodge job fix?
Yep... This is my conclusion so far. Carb re-built. Weak spark. I think the coil is bad and they thought it was just a spark plug. The ceramic part broke off so the PO though you just put another plug in the hole. I think from there they couldn't get it running and let it sit. Good compression. But no spark. New coil to come.
oh my god, that is the funniest hack job I have seen. Project is looking good. nice.
I think the hack job saved it to be honest. Of it had been running for the past 10 years who knows what kind of condition it would be in! The fact that the plastics are all there is amazing.
So having issues getting spark. Is the flywheel isn't spinning when it kicks over, but the motor does spin. Any ideas?

you should probably pull the flywheel and inspect the crank under there, see what the taper (i assume it is a taper fit) looks like. if the woodruff key is then try re-tourquing the flywheel down to the shaft. if it is warped or uneven you may have to lap it the same way you do a valve. paste, twist, repeat, until they are mated to each other then clean up and re-tourque.

or your crank could be snapped in there..... :-[
so I pulled the flywheel. I originally thought to myself I would need a puller to take it off. Turns out the K0 qa50's didn't have a woodruff key. They had a "pin" on the end of the shaft. It's stripped/worn off. Looking like I need a K0 crank shaft... Any grand ideas?
Drill it out replace it, looks like it is still available according to my favorite parts fiche.

the key doesn't hold it in place though, it should be tight enough to hold it in place with the taper. The key just helps line it up on the shaft when you first put it on.
that looks salvageable to me so good luck!!!
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