Hi, I've tried several time to adjust my valve clearances and had no luck, every time I do it my valves will make a loud ticking sound when the engine is running and the performance is slightly degraded. I am unsure if I am rotating my engine to the correct position; when I align the mark on the flywheel with the other mark on the crank case cover there is no free play in the rockers whereas when I rotate the engine a little further the rockers lift up a little more and there is some free play so at which point do I adjust the valve clearances?

I don't think my engine is in any danger because I have done a 100 mile road trip since I adjusted the valves which involved hard acceleration, red lining and full throttle for extended periods and the engine didn't explode but I want to be 100% sure on what to do before I adjust them again.

By the way my engine is a K157FMI which is used by Sinnis 125s, pulse adrenaline and many more.