I think but dont hold me to it but the 250es and the trx250 (not the x model) have the same rear end, also a 250sx (trike) has the same
thats the shaft drive right. the sticker on the frame of the bike says 1986 trx250x but that is the only 250 other than the trx250r so i guess it is the same. the rear end looked exactly the same though. and the engine is the same. do you know how wide a atc 250 big red is? i couldnt find that info.