I recently picked up an old yamaha from the mid ohio swap meet that I hope to have ready for the motocross next year. the problem is, I am having a really hard time figuring out exactly what it is. I was told that it was a 1976 but other than that the guy I bought it from had no idea. It has white plastics and tank, the tank says 125 but the cylinder is marked as 171cc, it has an odometer or speedo pickup on the front hub, twin shocks, it's not oil injected, the carb is a 34mm mikuni, the head has 2 spark plug holes, the frame and engine number is 565000445, and upon pulling the flywheel it has points and a lighting coil. I have looked around for a while online and can't figure it out. Any help would really be appreciated.