Bicycle wheels have been used on lightweight planes and ultralights, but they are a bit weak if loaded laterally (such as you would experience with a hard, fast turn on the ground or while landing with a crosswind or sideslip). I see BMX wheels used sometimes and I suspect they may be a little sturdier than the traditional spoked wheel.
Thank you duncan !! I looked at the site ,I have a 14" x2" spoke on the front and will have to find about the same for the back axle.looks like a bicycle wheel but would have to shim it up to fit!! could not find on the site.I'll have to look again!