Hi all, I'm trying to order new tyres from rocky mountain ATV for my DR650. Because of the type of wheels I have (spoked), I think I have to run tubes in my tyres. So I've got a couple of tyres in my cart, a 120/90-17 Tube Type Dunlop D404 and a Bridgestone Battlax BT45. Are these tyres any good? I'm on the tyre tube pages on the rocky mountain site at http://www.rockymountainatvmc.com/t...tle=Tires+and+Wheels&webTypeId=144&webCatId=8 , and I go to search by tyre tube size. There is no 120/90-17 tube size and there is no 90/90-21 tube size either - it seems as though tube sizes are different to tyre sizes, so what size tubes do I need for the tyres that I have in my cart? The Dunlop D404 is advertised as being a front tyre, but is it OK to put this on my rear wheel given that it is the correct size for the wheel? What is the difference between 120/90-17 and 120/90x17?