Hello all, new here. Just bought a older Yamaha from a guy. It look like it stepped right out of Mad Max....heavily modified frame, paint, etc. Problem is, no VIN in site (check the whole frame everywhere..took all plastic off). I DO have the engine serial still - 52H-031431. If anyone can help me identify the year, model, engine size, and any name it had back then it would be much appreciated! I need to find a service manual to fix a no spark problem but without knowing anything about this quad the service manual is hard to find. I'm guessing she's mid 80's. Thanks in advance for any help!