Motorcycle Repair: knocking noise from top of front cylinder, cam bearings, rod bearings

Question
I have a 92 sportster 1200 (evo engine) that has suddenly developed a knocking sound in the front cylinder. like a knuckle rapping on a desk.

It seemed to be coming from the pushrod side, so I took a chance and changed the tappets. When I put the bike back together, the tappets clicked for a while then settled down, and I was left with the original knocking noise. I took it for a 50 mile loop, the noise seems to be getting slowly louder.

The bike seems to perform well, idles smoothly, compression (using a harbor freight gadget) is 110psi in the back and 108 in the front.

Any thoughts would be appreciated.


Answer
Sorry I didnt answer you sooner. My hard drive decided to go south!
You might have to check your cam bearings as well as the rod bearings. Also, check the rockers.
I woul start by pulling the top end and as you go check each part until you find the problem
Good luck and happy riding
Mike