These are cool.
Invented by Michelin, Michelin Bib-Mousse has an unparalleled number of victories and championships: 26 victories in the Dakar Rally-Raid since 1983, 22 Enduro World Championship and 7 Motocross World Championships!
Michelin's Bib-Mousse is a foam core insert which replaces a standard rubber inner tube in off-road motorcycle tires. It is a sponge-like circle of butyl honeycomb foam whose tiny cells are charged with nitrogen. Lighter than a heavy duty tube, Michelin Bib-Mousse offers an equivalent pressure of 13 PSI (0.9 bar) and removes the inconvenience from a puncture. The smooth molded outer skin is designed to help it slip into its specified size of off-road motorcycle tire (Michelin tires ONLY). Developed by Michelin for expert racers who must finish each and every race. When you cannot tolerate a DNF, get Bib-Mousse!
Notes: Use only with Michelin off-road tires; because Bib-Mousse is shaped for a perfect fit inside Michelin tires, use of Bib-Mousse with other brands of tires can lead to handling instability and possible destruction of Bib-Mousse. Bib-Mousse is specifically designed for off-road competition use for speeds UP TO 80 MPH (130 km/h). Above this speed, heat build-up can lead to rapid destruction of the Bib-Mousse, resulting in serious injury to the rider. Under no circumstances should Bib-Mousse be fitted to motorcycles for on-road use.