aaaaahhhhh You only want one...hmmm...yes you are correct about the 4wd system. The diameter being slightly different will affect it...but .25 inch...I doubt. If youre in slick mud, all they will do is spin anyways. If youre going to ride in 4wd ALOT on hard pack stuff...I would stick with the same tire all the way around. If its only going to be situational, it might be fine to put different tires on the front than the rear. However, my question still lies...why not get something better than those tires. Im going to tell you right now I own 23'' Maxxis Bighorn 2.0s. I have the 23'' for xc racing purpose of lowering the quad and faster starting. Most people run the 25'' tires...why not go with the 25'' bighorns or bighorn 2.0?? Its really a great tire. As for the ohtsu tires...I just tried searching and on my web browser I see forum questions all over about how other people can't find these tires as well. I dont know what to tell you about that. If you still want a cheap cheap tire I would go with the carlisle badlands which is what mine came with stock. They make them 6ply and theyre really not bad for stockies. Anyways, good luck with the tire situation!