Nice. I remember buying an engine (TS125 as it happens) many years ago for a playbike transplant from this guy who assures me it was rebuilt by a reputable shop. It was v.cheap & I lifted the head to see no seizures & honed barrel so bought it.
Not being hugely trusting I pulled it a bit further apart & found circlip-pliers ring type circlips on the Piston, Hmm don’t think those will last at 9000rpm. Pull the flywheel & -oh looky -I can see the bearing (no seal), . . but they’ve left the bearing dust seal in, maybe they thought that would suffice. Maybe that’s why it didn’t start & they sold it.
Built by a reputable shop? Yeah sure buddy. Time to delve deeper, main bearings aren’t C3, gearbox selector shaft a sloppy fit so needs bushing so it will shift properly. At least it was cheap & I wasn’t some poor kid who couldn’t fix it.
Another funny story was my RZ350 roadbike was gaining gearbox oil. Heck I’ve overfilled the gearbox! What a Klutz, how did I do that? Then it happened again. What the?? Pull cover off & the auto 2 stroke pump’s seal had fallen out allowing the contents of the reservoir to slowly trickle into the gearbox. I glued the seal back in place.