do these symptoms suggest I need a valve adjustment? Edit: or bent valve?

[koko64]

+4 on all that. Really does sound like ass covering.
If those guys cant give you a true reading, they should have told you when they saw the mods. They still took your money though!

Just put the bigger main jets in. Too rich might cost five bucks in plugs, but too lean could cost you alot more (and as Lt Snyder says," you'll hate life"). Its the easiest jet to change and if you dont like it you can change back easily.

[Howie]

Enough said about "where the measurement is taken", Nate summed it up best.  As far as coil failure goes sounds like you might just have a weak coil.  Different load will require stronger spark.  Easy to pick up with a scope.  Run engine.  Pull plug wire and continually increase gap between plug and wire until you read maximum voltage, a new stock coil will put out between 19 and 20K volts.  I never see scopes used in motorcycle shops though.

[Rudemouthsky]

If the numbers are consistently off for a given distance from the exhaust valve, how does the tech know how much to "fudge" the numbers to get a "good" AFR?  Did they measure your exhaust (not somebody else's that kind of looked like it).

YES, That's the first doubt that crossed my mind.

+4 on all that. Really does sound like ass covering.
If those guys cant give you a true reading, they should have told you when they saw the mods. They still took your money though!

To be fair, I can only say these guys are potentially incompetent but not crooks. They haven't charged me a cent for the dyno time or "tuning". Now, I can see where this exhaust may make getting an accurate reading difficult, it has an "S" bend from one cylinder where it enters the can. But I guess that dude didn't wanna admit that, hence the bullsh**ing. I'm not averse to putting the jets in myself, but I wanted them to, since they have the dyno and could tune it. But I guess they can't tune it, lol.

Enough said about "where the measurement is taken", Nate summed it up best.  As far as coil failure goes sounds like you might just have a weak coil.

That's another thing I asked, why wasn't that discovered the last time they had the bike?

To clarify, they've had my bike on the dyno twice now and have not "tuned" or changed any of my settings. It's beginning to look like they don't properly know how to!  

Thanks ya'all. 

[Rudemouthsky]

Ok guys I could use some fast input because things just stopped being funny.

These guys called again. Said that the vert cylinder is still carboning up despite the replaced coil. I'm not surprised at that bc I didn't think there was anything wrong with the coil (although they're still insisting the coil was bad. Whatever)

Now they need my permission to check if the timing is off, as this is they're next hypothesis as to why the cylinder is carboning up.



I'm into it for $400 at this point...$250 for the valve adjust plus $150 in "diagnostics" aka them trying to figure out WTF is wrong.

Questions: if my timing is off, wouldn't the bike run like absolute shit, then proceed to wreak havoc on the valves and pistons, rather than run good for 100 miles, foul up a plug, run good for 100 miles, repeat, etc?

[Dirty Duc]

Gotta agree with DP.
I replied to your other thread. A valve adjustment is a good baseline however to even everything out before a carb tune. How long ago is a good question.
Could be too lean up high and too rich down low. With your mods your carbs need a tune.

This.  I'm far from a carby guru, but this sounds like the most reasonable explanation.

Assuming they are talking about ignition timing and not valve timing (you are talking about valve timing):

I don't know what you are running for ignition control, but IIRC the timing is essentially fixed for the early two valves.  Either way, I don't believe there is a way to separate the two cylinders (either both would be bad or both would be good).

[koko64]

Didnt know you haven't paid yet or that they still have the bike, so fair enough I take that back (at present). So they did the valve adjustment?
Do these guys usually work on Ducatis? I would think about that re the valve adjustment. It would also be best for someone who knows carbs and FCRs to tune them. Some dirtbike shops may be very familiar with FCRs which gives options.

[Rudemouthsky]

Its at a Ducati dealership/service dept.

They are currently suggesting the carbon build up could be being caused by incorrect VALVE timing.

This is what has me all FUBAR at the moment.

[koko64]

Ok then, the valves are done.
The valve timing being out means not enough to blow up your motor and the timing dots line up from the factory, so stock oem. They can be out from spec and one cylinder from the other. Brad dialed the timing on my bike and speeddog just did his and they run smoother. You can set them to spec or advance them like Brad which improves response and got me 2 hp. Maybe it may help a little with your groovy exhaust to even things up. Edit:  Actually, your exhaust may also, in theory, require different cam timing on each cylinder to accommodate the asymmetric design. Imagine the time and money doing that on the dyno!. If they want to dial in the cams I would have them advanced ala Brad.
It depends how much you want to spend. Edit :Get a price on that, checking and adjusting.

I think your funky exhaust means you need a different setting on the slow fuel circuit on the offending cylinder. I cant remember if your carbs are synched either.

Me, I'd fit bigger main jets and open the slow air jet screw a quarter turn on the fouling cylinder and try that.

[Rudemouthsky]

   Apparently I have other concerns aside from the carbs needing to be properly tuned. Just as soon as the bike is back in my possession, I will be swapping out the jets and adjusting the slow air screw. But in the meantime, the shop has determined the cause of my vert plug fouling to be a worn valve guide. So I'm looking at a new valve guides plus having the seats cut.

I'm not too happy with myself for not noticing this when I was in the best possible position to have it taken care of...out of the engine and in my hands.  

So....can anyone tell me if these 2 different heads would swap into my '96 engine? seems a better way to go than paying for valve guides and seating...man this is soooo fu**d . One claims is from a 93-95 Elefant the other vintage 98...

http://www.ebay.com/itm/1998-era-Ducati-900-Monster-30120181CA-vertical-cylinder-head-with-guides-NEW-/161131495496?pt=Motorcycles_Parts_Accessories&hash=item25842f8048&vxp=mtr

http://www.ebay.com/itm/1993-1995-Ducati-900-Elefant-30120431A-horizontal-cylinder-head-with-guides-NEW-/171153727088?pt=Motorcycles_Parts_Accessories&hash=item27d98e9e70&vxp=mtr

I do think they are telling me the truth btw...

with some of the symptoms running through my brain (smoke from vert.cylinder exhaust, random poor running issues, occasional hard start, backfire...meh. I really should have gone over that motor much better.

[ducpainter]

Both of those heads are stamped with a W which signifies smaller valves.

I believe the 96 heads on your motor should be stamped V which signifies larger valves.

You don't want to mix and match.

FWIW I don't think the bad guides are the root cause of your issues.

[Rudemouthsky]

Both of those heads are stamped with a W which signifies smaller valves.

I believe the 96 heads on your motor should be stamped V which signifies larger valves.

You don't want to mix and match.

FWIW I don't think the bad guides are the root cause of your issues.

Perhaps not...but this plug fouling came from nowhere. That tells me maybe it *isn't* the carbs, since it was running fine for awhile, albeit low on power. And now I can rule out wires and coils. So, that all adds up to: 

[ducpainter]

Perhaps not...but this plug fouling came from nowhere. That tells me maybe it *isn't* the carbs, since it was running fine for awhile, albeit low on power. And now I can rule out wires and coils. So, that all adds up to: 

Has the shop done a leakdown or  compression test?

[Rudemouthsky]

Has the shop done a leakdown or  compression test?

Yes, leakdown. I don't have the results here with me. I'll be talking to them more soon.

[ducpainter]

Was this test just performed or had they done it earlier in the diagnosis process?

[Rudemouthsky]

Was this test just performed or had they done it earlier in the diagnosis process?

They did not do it earlier in the process. That's one of the things I was upset about when I paid them a visit, Was being billed diagnostic time to chase down a supposedly bad coil (replacing of which didn't solve my problem - so I doubt my coil was *really* an issue) Then being sold a valve job... then being billed to check cam timing (timing was just FINE btw)....and THEN being told about my valve guide issue.

Typing all this out...I find myself getting pissed off again, lol. But we came to an agreement that I feel is pretty fair....so I'll bite my tongue for now....and we shall see what happens next.