There are only 2 sizes of cast spokes...20 and 22inch. 22.5 tubeless go on 20" spoke and 24.5 go on 22". The comparable tire to an 8.25x20 is a 9.00x22.5 which is almost obsolete. 10x22.5 tires are common on bobtails and 11x22.5 is pretty common. However the low pro 22.5 is the most common these days. It is about the same diameter as a 9.00x20. You will need 22.5 open center rims. 8.25 wide if you run 11.225 or 7.50 if you run 10x22.5. A few years open center wheels were every where in fact 20 years ago I had over 300 of them on the ground. However now they are getting scarce. I wish I had kept a few. You may have to get a wider spacer to run larger tires. You want to make sure the duals do not touch when you are loaded I always ran 4" wide spacers in fact I have a bunch of them in the warehouse. If you go to a wider spacer, you will need a shallower cleat. You never want a cleat to bottom out on the hub or it will slip
Last edited by crenwelge; 10/05/2009 8:02 AM.
