Sounds like the cam chain tensioner to me. Pull that side cover and have a look, when the tensioner isn't working right the chain can start to eat its way through the guide. Also pull the tensioner itself and check that it smoothly extends and retracts. If your taking things apart its good practice to put a zip tie through the chain and snug it up so you have no chance of it being loose and skipping a tooth... something you dont want to happen without you knowing it.
thanks for your reply. Will oil drop off when I'll remove the cover?
so I took the cam chain tensioner off and this is what it looked like.
From what I understand it should spring back when i release it but it doesn't. So i suppose it is done and I need a new one. So I did put it back and started the bike.
but the bike didn't start. I went on for 1 sec and then stop. sounded like the cam chain was stuck. So I removed the cover and tried to turn it around but it wouldn't move. I the fiddled with it a bit, looked like there was a skipped tooth stuck there. Back and forth and finally I manage to free the tooth. Started the bike and it worked. the tensioner somehow now doesn't make nay noise but bloody hell I have a clicking noise coming for the other side of the engine now!!!
Did I mess something up while trying to free the cam chain?
:-/
22000 miles and I haven't check the valves yet. I want to get a new bike soon so if I can avoid that expense I gladly do so mbut I need to get rid of the noise. :-/
Mine doesn't come out at all. stays in place if you screw it in and in place if you screw it out. looks like the spring may be broken.