Aprilia made a prototype fuel cell Bike, a while ago,
Gore + Aprilia Fuel Cell Bike : TreeHugger
IMO They missed the mark & should have built it to replace the old 2 stroke Derny mopeds
which are still used for motor paced Keirin races on indoor tracks .. velodromes..
It has been shown thru many ..leave the car running in the home-garage suicides ,
the CO exhaust fumes of the internal combustion engine in a confined space is not very healthy..