Hi, l am looking to buy a vinduro bike, l was looking at a Xr 250 86 model or 87 model to me they are very similiar to the 85 and 84 models, how fare can one go with the XR before they are not eligible. Because l don`t want to waste my money on purchasing a bike that can`t be run, It would have saved a lot of problem if they just made the cut of dates pre 90.