I have an 06 zx14 that I bought about a month ago. Since it's new to me I'm always listening to the engine for noise. Just trying to figure out what is normal and was isn't. I did change to a manual chain tensioner and that completely fixed the startup rattle. That said I can hear a slight tick in the topend around 2500 RPMs. Nothing bad "most people can't hear it" but it's there. It almost sounds like when they reshimmed the valves they may of got one or two a bit on the loose side. Now that said my yamaha vmax 1200 ticks louder by far and has for the last 10 years. Also was wondering what that large piece of rubber on top the valve cover and down the side of the head is for because it was torn up pretty bad. Guessing the dealer that done the valves got a bit wild with that rubber cover. So last week I added the washers to my valve cover to stop the common oil leak "which fixed it" I just removed that thin rubber that was all messed up. Since I did that I noticed the slight tick. Is it possible that rubber cover over the engine is there to insulate the sound from the engine?