Yo, that hit his hand, forearm area... not his chest (i don't think) looked like it broke his forearm in 2. It blew up...he grabs his left arm... with his right hand... and them falls over...

"Single piston theory"
As he was about to speed off down the drag strip there was a sound from the grassy noel area, and a puff of smoke...
The piston entered his left hand made a 90 degree turn then entered his left chest, made a 45 degree turn, exited his right shoulder, turned right, not left, struck the other rider in the shoulder and then proceeded down his left arm to exit around his wrist... the piston then travels down the drag strip and grazes a man standing with an umbrella in the forehead. Only to find the pristine piston on the stretcher some 4 hours later...?