ZR engine-related. Did I screw up?

I realize this site pertains to KZs, but hopefully I won't get in trouble for posting a question about another "old school" Kawasaki engine.
This past weekend I decided to check the valves on my ZR-7.
A couple of them were tight, so I made the shim changes. Upon re-assembly I put the exhaust cam 180 degrees off.
Without realizing what I had done, I turned the crank over with a wrench so I could recheck the clearances. Upon doing so I heard a loud "POP".
When I got home tonight my worst fears were realized. I found a new compression gauge with the 12mm adapter I needed so I checked all four cylinders and not one of them had enough compression to move the needle. After checking cylinder #4 I removed the gauge and stuck my thumb over the spark plug hole and hit the starter button. There was just barely enough there to make a slight puffing noise. El Crappo!
FWIW, I performed the compression check with a cold engine and without the carbs mounted.
So have I royally screwed up or what?
Thanks for your pity and replies. :sick:
Jim

I am afraid you probally bent some valves when you turned the engine over with the cam in 180 degree's out....
Had a friend of mine do the same thing with his KZ except he used the starter and bent them all good..

Anyway that Sucks big time, tear it down and tell us what you find

1045

1045 wrote:

I am afraid you probally bent some valves when you turned the engine over with the cam in 180 degree's out....
Had a friend of mine do the same thing with his KZ except he used the starter and bent them all good..

Anyway that Sucks big time, tear it down and tell us what you find
yeah,that sucks!
1045

:S

I dont know about youre peticular bike, but i could install my cams eithier way just by fliping them over.
really did not seem to make much difference. sounds like to me you lined them up on the wrong mark. which
could do more than just bend em. I would take the cams back out and really try to find the right timing mark
you might find you got lucky.

Well at this time I'm very unhappy to report that Lady Luck has not been at my side.
Today I removed the head from my ZR7 and poured water through the exhaust ports and NO LEAKS! :woohoo: Inverted the head and did the same with the intake side and, of course all four leaked! I plan on replacing all eight valves and seals and of course the head gasket. I figure it will cost about $350 or so. OUCH!!
On the bright side, I'll now be able to clean up the combustion chambers because they REALLY need it. This bike has been running way too rich for a couple of years now.
Jim