The framework is the easy part. The more challenging is the axle, because bearings that fit over 0.922 actual OD of the pipe or inside the .844 ID of EMT tubing are none standard. Not sure how you were planning on implementing the wheel axle on the frame, but if you were planning to keep it all in-line on the same plane, you may need to get a bit creative with the conduit tube ID/OD by using adapter rings or sleeves, as I used on my Go-Kart using 3/4 EMT tubing as the main drive rear wheels shaft. I think a one wheel hover board works best with the pivot (Axle) on a higher plane than the stand for better stability.
Mario I. Arguello
Engineer - Designer - Artist / Owner of MIA Micro-FLIGHT