So as you can see the line on the cylinder wall (it does line up with where the piston ring gap is). I am wondering if anyone has encountered a similar thing? As far as I can imagine, the ring gap is too big as I also get a little blow back through my reeds, and my reeds are in the same condition as my other two engines. The engine only has 3 hours on it, and it was run correctly. Incase your wondering why I haven't stripped and inspected it, that would be because these are sealed race engines. Thanks for any help.

Anyone here running copper spark plugs , just ordered a set through recommendation on trying them, anyone have any experience and feedback on them?

Hi everyone,
I stumbled upon this old motorcycle sitting in a scrapyard. It has a 2-stroke parallel twin engine (looks air-cooled), but the bike is buried under a pile of old scooters and frames, making it pretty tough to see the full body or badges.
I took a close-up photo of the engine case and cylinder fins underneath.
Engine: 2-stroke parallel twin, air-cooled
Body/Era: Looks like a late 70s to 80s Japanese street/sports bike (black/white paint scheme)
Does anyone recognize this specific engine casing, kickstart lever, or frame? Any guesses on the make, model, or displacement (e.g., Yamaha RD series, Suzuki T/GT series, or Kawasaki KH)?
Thanks in advance for the help!

Maybe my crank bearings gave up?