Yea I figure the rim size will be a few inches less than the ending "size". The real question will be resistance, and if it takes more force to move them. The car tires are scheduled to come out mid August I believe. Somone will do a fuel consumption test on them, and we should know how effecient they are at that point. Solid tires kill performance and I expect these to be a touch less efficent than current tube/tires, but if they can get it close it may be worth it.
http://wfxd.com/featured/12488/new-s...ms-and-no-air/