Just completed 1973 125 Six Day

[michajon]

Started this project in May of 2024. I just finished it and thought I'd share it with the forum. The Frame date code is April 1973. The engine is a 6B with a Mikuni VM28.

[Stuttgartautoman]

Nice job Michajon. Can't wait to hear it ripping at AHRMA cross country races. 😎

[Doug Knight]

Mike, not bad, I recognize a lot of parts combinations that I sent you along with. Nice choice on the rims. How does it run and start? I found some other parts belong to this project, shoot me your shipping address again. I've been dealing with health issues that are now clearing up. I'll be parting my 4 Jackpiners and Hare Scrambler later this spring.

[Admangia]

This looks fantastic. Really nice work. Will be looking at that a few hundred more times! I have a 1973 manufactured March of that year and hope to learn more about the brand and bike. I am vexed as whether to race/ ride a few times then attempt restore or just get busy and restore while all parts in working order. Recommendation from your own experiences with this project most certainly welcomed! Beautiful, heirloom quality restore!
Andrew

[motograndpa]

Very nice job! What was the biggest challenge for you in this restoration?

[KJDonovan]

Great looking build!  What did you use for a spigot adaptor for the Mikuni?  I can't quite see it in the picture.

[michajon]

Thanks for all the really nice comments. It all helps make the experience even better.

The question about the carb adapter - using a lathe, I shortened the carb exit and turned the O.D. Then I made the stub adapter. It slips onto the carb exit and is bonded. It's now part of the carb. The other end going to the cylinder has an internal O-ring to seal with the intake manifold tube. The bore is tapered match the two I.D.s It is split so the clamp grips the intake manifold to hold it in place.

The question "what was the biggest challenge?" - So many challenges! Aligning the clutch plates and getting the clutch back on the spline is a challenge. Most things are not so much difficult as they are just very time consuming. Painting the tank, air box, and side panel for example. Doing it myself was a couple of weeks. I built a make shift paint booth in my back yard. Several trips to the automotive paint store finding the color. FYI - the brand makes a difference too. Prep, paint, clear coat, decals, lots of steps. Swing arm bearings require a substantial press (not just a hand arbor press). It also requires a proper support. So making some custom tooling is sometimes required. You may need to make bushings for the shocks; heat form, shape and match drill fenders; straighten and or weld some parts. It all depends on how complete and what condition is the bike or parts you start with. It can be very satisfying. Here's a couple of progress pics setting the timing and fitting the rear fender and exhaust.