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Here is just a few key points.
1) High compression engines tend to make a hissing sound as the the pistons are coming up on compression stroke when turned by hand with the spark plugs installed. This is the cylinder pressure passing the rings and entering the crankcase. This does not indicate a problem by itself. Since the piston is moving so slow turned by hand it allows time for pressure to leak past the rings. Even in engines with good rings you still get some hiss sound.
2) Bad sealing intake valves would cause noise and or pooping in the intake.
3) Bad sealing exhaust valves would cause missfire sensation at idle that would tend to smooth out as RPM increased.
4) cyclinder leakdown test should be performed with the engine as warm as possible. Cylinder bores are not true round when cold, and pistons are not at there full heated size.
5) During a leak down test, air leaking can be narrowed to specific areas. air noise in the intake is possible bad intake valves, air noise in the exhaust pipe is possible bad exhaust valve, noise from oil fill hole is possible worn rings/walls.
6) If bad rings are suspected a second leak test should be performed. Add a tsp or so of engine oil to the suspect cylinder and turn the engine over a few time before the second test. If the leak rate gets lower/improves it is most likely rings.
7)Valve leak can be bench tested with a light/thin fluid such as brake clean. with the head off You can fill the suspected port with fluid and see if it leaks past the valve when the valve is closed. if it does you have a bad valve or seat. If it holds fluid it is most likely good.
8) and finally if it sounds fishy, smells fishy, looks fishy it probably is. Look around the shop and see how much work they have. A dead shop sometimes indicates what you're about to find out.
 

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Good to here everything sounds legit. I've read on this and other forums about the valves recessing into the head is quite common on ducatis. I still don't see how valves pulling up into the head is considered normal wear at lower miles. I've see auto manufactures provided customer satisfaction recalls on such things till 100,000 miles. It should be considered a design/material defect and get a little factory assistance
 
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