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Hi, I'm new to the forum. Until now I've beem fiddling about with my Honda CT90. Today I was at the recycle shop at the local rubbish tip and picked up a Yamaha 80 off road bike for $40. I took it to be a YZ 80 but on checking up the engine number (367-65XXXXX) on the net it appears it is a GTMX 80. Can anyone enlighten me on the year and what is the difference between the GTMX and YZ as they seem to have been made concurrently. Are there any common parts as there seems to be plenty of parts for the YZ around? It is complete except for fuel tank, gear lever, seat and the round plate on the LHS which shows a plate with an electrical coil but I assume the magneto? is missing. Any help would be greatly appreciated.