are you saying here that it will run on each cylinder when other is grounded out?The rods were bent and the seal on the spring was out. Yes the push rods. The spark plug works just checked that. I'm seeing light black exhaust coming out too.
I just put a used tec vtwin on a friend's mower and I got some backfire and miss . I used my laser temp gauge on the exhaust pipes and found one was not hot so i knew that cylinder was not working.