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New gasket...use nothing.
Looks like something certainly rattled around in that combustion chamber briefly. Maybe escaped into the exhaust??

With the cams out, turn the head on edge and fill the ports with fluid (like parts cleaner or gasoline) and watch for leakage into the combustion chamber. Do the intakes, turn it over and do the exhaust. You should see no (or extremely little) fluid coming past the valves. If they aren't sealing now is the time to address that.
 

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Discussion Starter #42
Yes I have done that on both intake and exhaust valves no leakage anywhere I think I have been extremely lucky
 

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Clean it all up..smooth out any sharp edges in the combustion chamber best you can.
Measure and inspect everything you can and put it back together.
How were your valve clearances?? and no score marks in the cylinders visible when pistons are at bottom?
Now would be a good time to measure the the timing chain for stretch, too.
 

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Discussion Starter #45
No I checked all 4 cylinders nice and smooth no marks at all, I will give everything a good clean up . All valve clearances were in spec just!
mv spec 0.2-0.29 ex 0.15-0.24 inlet
mine 0.2 0.15
maybe they are a bit tight would this cause a ticking?
I did check chain and tensioner and was all good,tensioner only out 3 clicks
 

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No worries then.... valves do get tighter over time, not looser...but that isn't your sound
Did you try to shake your exhaust pipes to see if anything (the wayward wellnut) would fall out?
 

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Discussion Starter #48
Cleaned everything up and getting ready to start rebuilding, just checked clearance again from piston to head using the 1.3mm gasket instead of the 1.45mm and it’s leaving me with just 0.031” or 0.80mm is that to tight. If it is would it be possible to double up the gaskets to give more clearance or would that only create more problems?
 

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I think you will be OK.
Here is an interesting article by one of my favorite technical writers. Google can reveal much more information.

 

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Discussion Starter #51
Some good news at last found what the ticking noise was a bent exhaust valve as seen here on the right in picture. It was in the chamber that had marks. I was not happy putting bike back together not knowing what the ticking noise was ,when I read that it all depends what position valve was in the head when it was removed as valve constantly rotates when engine running that it is why I had no leaks with fluid or leak down test as it was seated in correct spot. When I removed valve and spun it in hole it only seated correctly in one particular spot. Now just to get new valve lapped in
 

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Well done finding it whilst you had head off. Looking at the impact marks on piston something metalic has been injested and then caused the valve to bend as.
Just a thought, have a look at the butterflies on the throttle bodies, I think there are two small screws on the centre of each on each cylinder attaching to spindle. If one of those has worked loose and dropped into inlet that may be your answer having same affect as Noel's well nut issue....
 

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Discussion Starter #53
Yes thanks had a look 2 screws still intact on all 4 butterflies, must have been brass wellnut from airbox and it must have went out exhaust valve into exhaust, so lucky not more damage was caused!
 

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Yes...well done finding the bent valve...I thought I saw some witness marks that may have indicated valve to piston contact, but wasn't sure and said nothing.
JensonF4...it was an air box cover well nut that fell in causing the damage....go back to the start of the thread for details.
 

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Discussion Starter #55
since I have head off should I take the Valves out of the other 3 chambers and reseat them or just leave well enough alone?
 

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Leave them alone !!! They are happily mated together.
 

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Discussion Starter #58
Another update on progress, new 1.30mm head gasket arrived today so ready to start rebuild, I was just wondering will the timing be affected going down .015 mm in thickness or will stock timing be ok for Ptv clearance?
 

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Wow I didn't think about the well nut becoming a problem at all. would it b possible to put a small mesh screen that'll act as a safety barrier in case of such incident or would it restrict airflow to much?
 

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Discussion Starter #60
No don’t think that would work as mesh would have to be very small to stop nut going through affecting air flow
 
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