Or does it even matter?

They will be Sand Stars for a YFZ 450 and a Raptor 350.

Thanks for your help.

 

10inch rim if you just like to have fun. as opposed to be concerned with having the tire grow a little at high speeds.

 

20x10x10

 

I've got 20x11x10 Holeshots on my 250R and I have no complaints. If your going to be trail riding and have an extended axle get a 10 inch wide tire but if you have the stock axle an 11 inch width will give you more bite. As far as a 10 or 9 inch rim, I think the 10 incher has more of a stylish look so if your going to be riding in the dunes and don't have to worry about getting big dings and bends on them from trees and rocks, get the 20x11x10.