so i just bought another 250 this past weekend. its a 85-86 and this is the first of those years that i have ever had. today i was stripping down the frame to bare metal for powder coating and i noticed that there is no vin# stamped into the vin plate. the plate is there exactly where it should be and is in perfect condition. it hasnt been ground down to erase the number or tampered with in any way as you would see if it where a stolen bike. im wondering if this is a replacement frame from factory. but i would think if it was it should still have a vin for that frame, right? any insight into this guys?