Sigurd Tjøsvoll, from Åkerhavn on Karmøy, made several versions of a monowheel where the driver sat inside the wheel. The first of these appeared in 1928 and was followed by others powered by single- and twin-cylinder (Douglas 350) petrol engines and an electric motor.
The engine, seat, footrests and a steering mechanism which caused the wheel to tilt were inside the circumference. Sigurd claimed the top speed was 200 km/h, and was not exaggerating when he added that the brakes were a considerable problem.
Tjøsvoll was quite the inventor and had several patents, one of which was for a device named "folkeflyet" which received considerable attention. It had the appearance of a bewildered Darlek.
Source: Norskproduserte Motorsykler