I'm not familiar with the YT125, but in addition to the VIN on the neck, there should be a VIN on the engine.
Usually on a flat spot at the base of the cylinder, or on top of the bottom end... somewhere on the "primary" engine case.
You can see if the neck numbers match the Engine VIN, the old Yamahas had short VINs 9 digits I think.
Edit: according to this:
http://www.johnnystoybox.com/parts_cross.htm
A 3x3 VIN is a YT125G, Yamaha designated each model year with a new letter afterwards, YT125G is a 1980.
Last edited by emmie357; 03-11-2014 at 08:17 PM.
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