These are pictures of a blown up Kawasaki Police engine (1996) with approximately 82K miles on it. It was in use as a Funeral Escort motor at the time of its demise. The owner said that it had been making a ticking sound for a while, then on the freeway it let loose. He rode it off the freeway and called for a tow. When I got it, the #2 spark plug was jammed in the hole. The aluminum chunks that came out of the pipe and carb on teardown weren't a good sign either. The exhaust valve head was sitting on top of the piston when I pulled the head off. The valve guide was completely out of the head. My theory is who ever did the last rebuild on this motor trimmed too much off the valve stem, allowing the tappet bucket to push on the valve keepers and popped them off, dropping the valve into the motor. When I checked the stem top to keeper top, they were flush. After a few thousand cycles, the head broke off and really beat the hell out of the piston and head. The more observant of you will notice that this head is wrong for this model, it's off a 1983 GPZ1100 (note the sensor for the fuel injection).

Kawasaki Police Motorcycle cylinder head showing extensive damage caused by broken valve. The exhaust valve is shown at the bottom and right of the picture. Note this head is not the OEM head for this model, has a temp sensor

Kawasaki Police Motorcycle piston top after exhaust valve beat it to death.