It doesn't work that way against the computer screen, silly.
sounds like a rocker arm might be bent. does it increase with rpm?
Could be... but even for something that simple, the motor will need to be rotated at the very least. I've given up rotating the motor for any reason and just pull the frame completely off.
Once most people realize that, especially if they not up to the task or realize no other motorcycle mechanic wants to touch it, or the amount of $$$ they want to, makes it just wind up on craigslist.
Try listening with either a solid piece of wood or a stethoscope for this purpose, you can also use a rubber tube.