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Discussion Starter · #1 ·
Alright. Where do I start....
Took my 1198 in for the 7500 mile maintenance, the dealer breaks I. Down to start the valve check and said they heard quite a bit of air while turning the engine over. After a pressure drop test, I get a call saying they found 34% leak down in the horizontal cylinder and about 28% in the vertical cylinder. I gave them the okay to pull the heads off and check the exhaust valves (which is what they were suspecting). Now that the heads are off, they're saying I need to replace ALL of my valves, and that I have some minor scoring on the cylinder walls. Which they suspect to by caused by the piston rings. Now I'm lost. I've already raccked up a healthy bill just by them pulling the heads, but if they have to pull pistons, it would get ridiculous.

From my knoledge on cars, you can tell when piston rings go bad because of oil consumption, blue smoke and that sort of stuff, but I don't have that issue on the 1198. Sounds to me like I'm getting the run around? Some opinions would be greatly appreciated
 

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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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Discussion Starter · #3 ·
I ended up running down to the shop on Thursday to take a look at everything, being as nothing that they said was making sense. The guy that had called me was basically reading off of a paper and didn't know exactly what was going on, so he grabbed the guy working on it. All 4 exhaust valves had recessed I to the head, that's where the lack of compression was coming from. Intake valves had some nasty deposits on the tops, a little bit of wear on the face, but nothing to worry about to me. There was a few scuffs on the cylinder wall, but they were above the piston travel, telling me I had something in the air or gas.

Tech just wanted to replace rings as a preventative making since the cylinders were already off.

She's been a bit hoppy at low rpms for quite a while...but so is any manual at a low rpm. I noticed that since my trip from VA to IL that it's been a bit hard to start. (having to open the throttle a little) which does tell me compression loss.

Shop isn't shady, just a little bit of words getting twisted.
 

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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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Valve recession seems to be more of a problem on bikes that are tracked but 7500 miles is not a lot of miles either way.

The tuner I use told me that the valves are often out at the first check as they regress a little from new, but once set at the first check, they rarely regress more unless heavily tracked or bike has run lean

Can the valve seats not just be cleaned up with a cutting compound to get a good seal ? I have done that on an aprilia rsv engine that had leaking valves and got a perfect seal.
 

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You may want to find out who does performance work on ducati in your area and have the heads reworked with new seats and a light port job while you already have it all apart.
Scuffing above the ring area is from carbon build up not rings. Clean it up, don't ride short trips on a cold motor, and don't store it with a full tank of fuel for long periods of time so you are running fresh fuel.

If Ducati actually stands behind this motor I'd be shocked. Unless of course, they are physically standing behind it while they laugh and tell you to f off and bring more money.
 

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Discussion Starter · #9 ·
I took it to my local dealer for the work. Performance work...hard to say who does it around my area. I havent really looked. Tech said the build up is common if you keep them at lower rpm, which i rarely get it above 6k unless im out riding on the weekends. Note to self/lesson learned. But the dealer is doing the head work to get everything back in spec.

I know that i will be running fuel sys cleaner through everyone in a while. I should have taken a picture of those valves and inside of the head so i could post it on here. Its by far the worst i've seen. Even from working on cars.
 
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