Hi Andy,

Let me rewind up.

Like maybe of us here, I love NSRs and was lucky enough to be able to purchase one.

I have purchased a NSR250 MC21 and it's in need of being restored. She's not running as she is half assembled and quite tired.

I started looking up MC21 parts and in the process noticed that the engine number falls into the range of a MC28. This surprised me since the bike was sold to me as a MC21. More importantly, the frame, fuel tank and instrument clocks are indeed all MC21 parts! I was thinking perhaps the engine number is incorrect, or perhaps it's a mutant bike.

This leads me on to believe that the next step for me on the journey of restoring this motorcycle is to truly identify what engine I have so that I can follow the corresponding parts and info on rebuilding/tuning.

So I have started this thread to look for other factors to identify if I have a MC21 or MC28, besides from the engine number itself....

I hope this helps clarity where I'm trying to go with this thread!