Clown bicycles are not new. But maybe these are new. I envision their use being at the circus, but also between acts at a Monster Truck Show. For those foreigners who are not familar with Monster Truck Shows, I suggest such an event be added to your list of things to do while visiting the USA.
Breakaway multibike. This would be a bicycle built for 7. The clowns would come out and peddle aggressively, showing off the speed and superiority of their vehicle. Pieces of this bike can break away, triggered by hidden levers. The bike falls apart bit by bit from the rear forward. As each clown loses his or her bike, he climbs forward onto the clown in front, which complains and gripes about the invasion of space. Ultimately all 7 clowns are piled on the remaining little bike.
2. Car crushing tricycle. I envision laterally compressed zorbs as the wheels of this tricycle, "pedalled" by a baby clown. It would have a horn and a basket. It would run over anything and everything. It might then be set bouncing.
3: Tricycle jumped over 30 parked cars. This would occur immediately after a truck or motorcycle completed such a jump. Much boasting and squawking would precede. The tricycle would fall off of the jump into a pit just in front of it, clearing no cars at all. The clown would then emerge triumphantly from the pit, with the same musical accompaniment given the previously successful real jump.