1980 Yamaha MX100 - $100 Rebuild

Hey guys, I just picked up this little thing off of Kijiji for free. He even delivered it right to our shop!
It's definitely not a cafe racer and it will never hit the street but it's a restoration nonetheless.

Aiming to redo the bike for less than $100 just to make it fun. I will be giving the bike to my wife when it's done so it'll be a cool little surprise.

Here's how I got it:




After a few minutes:


It was still missing lots of pieces at this point so I wasn't sure what I should do with it. Tank, pipe, piston rings, rod bearing, and side covers missing. A few hours later he texted me and said he forgot to give me everything.
So he stopped by with this:


More loose stacking of pieces and voila! A complete looking MX100.






It's even got the '84 plate on it still.

So as it stands it has spark, the bottom end spins free, and I have almost all the parts.
The carb slide is stuck in the bore, the bars are mangled, I ordered a rod bearing and rings, and I still need to order cylinder gaskets and a wrist pin circlip.

Current total: $38.05

find out what the bore is I may have a nos piston or two but rings may be an issue

~kop

Awesome, its still got the stock 52 mm bore.

got em , let me know if you need a std + rings or if it needs an overbore .
You may need just rings .
Have the right guy check ring end gap if you can't and determine if bore is too sloppy .
Word of caution here , if the bore clearance approaches anything like .004"+ you risk breaking the piston skirt off . This leaves a huge mess .

~kop