ROCKET CYCLES! #1: Fritz von Opel

It's summertime, and a young man's fancy turns to... attaching rockets to his motorcycle! Except, in each of these cases, a middle-aged man is actually behind the project, which lends a Freudian question mark to their motives...

In 1928, Fritz von Opel, founder of the Opel car and motorcycle works, began experimenting with attaching rockets to his racing cars, a special high-speed train car, an airplane, and a Neander/Opel motorcycle. The bike in question was a MotoClub 500SS (Opel bought out Neander and badged the bike as their own), to which 6 solid-propellant rockets (with a thrust capacity of 66lbs combined) were attached. The rider activated the rockets with a foot pedal, after using the motorcycle's engine to reach 75mph; Opel calculated that 220km/h (132mph) was then possible. The World Motorcycle Speed Record in 1928 was held by O.M. Baldwin on his 996cc Zenith- JAP, at 124.5mph (taken at Arpajon, France).
On May 19, 1928, the machine (dubbed 'the Monster', for obvious reasons) was demonstrated at the Hamborner Radrennbahn, so much smoky effect, before a crowd of 7000.

Note in this photo that a dozen rockets have been added - doubling the capacity from the above photo. It was thought the machine would be used for a world's land speed record, but obviously, strapping on rockets isn't a guarantee of success even in a straight line... German authorities thought so as well, and forbade the use of the rocket-cycle for a speed attempt on the grounds of safety. Opel had success with his other rocket-propelled experiments (the car and airplane - -RAK1- especially), so was satisfied to lay the motorcycle aside after a few demonstration runs.
[This info comes from a fantastic book; 'Opel-Motorrader aus drei Jahhrzehnten', 2001, by Jurgen Noll, published by Heel]