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As wear patterns on both lobes are identical I'd say that the cam was finish ground on the grinding machine with the wheels being not flat. (the periodic diamond dressing was done wrong)

Run it!
 

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Do you have more clearance on the side that isn't burnished?
 

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Discussion Starter #4
Do you have more clearance on the side that isn't burnished?
As I measured clearance with a feeler gauge of .5" width there was difficulty in isolating just that one side but clearly there is more lash as shown by the wear pattern.
I have to guess at this point that basic machining was not set-up properly and the centerline of the camshafts are not co-axial with the rocker shafts.
The rear cyl. also shows some of this wear pattern as well.

I guess the real question is the valve actuation being springless MIGHT mean that there is less pressure on the cam lobe which MAY allow this partial contact area to survive the clearly sloppy machining techniques performed on these heads.

I wonder if the align boring of the head casting is at fault here???

Oh well, kinda what you expect from Ducati race shop! Brilliant design, sloppy build!

Fretka
 

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Or the follower shaft is not parallel to the cam shaft. If the wheel needed dressing the surface of the cam may show progressive wear from where the cam enters the grinding wheel and then when the cam actually leaves the grinding wheel. A grinding form like that would be from plunge grinding, not the most accurate method. But it’s possible.
 

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Discussion Starter #6
After speaking with my "internal combustion mentor/wizard" I am now of the belief what we see here is a direct consequence of belt tension.

I set the belts at 110 hz (sound) as I was told was correct, but I am thinking that was too tight.
What is the latest tension #'s for the testa motor?

TIA...........
 

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That seems unlikely to me... The amount of tension needed to shift the cam like that would be immense, enough to snap the belt easily. Could be wrong though, I'm not an expert when it comes to Testas.

I would keep a close eye on the rocker surfaces. Believe it or not they can flake - it's rare but it does happen (I've seen it firsthand). Having an uneven wear pattern might make it more likely.
 

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Oh, one more thing - loosen the cam journals slightly and re-torque them to spec in a cris-cross pattern. You never know, they might have been improperly torqued during a valve adjustment (or even at the factory).
 

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Wow. I too can't see belt tension being the culprit 110 hz isn't that much IMHO.

The wear indicates a missalignment, as stated could be the actual heads or more likely the cams.

What do the belts, cam gears and rockers look like?

And recommend tension low to high is 80 to 115hz
 

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Discussion Starter #10
I agree, belt tension remains at 87 hz.

I checked camshaft journal lash and it shows .0001 which is fine by me.
Rockers, lobes etc. all look fine so I'm gonna guess that their just isn't much I can do about it.
The bike shows around 10K miles and I suppose if it were going to frag it would have done so by now.
I did notice wear patterns on all the other cam lobes and while some were off center, they all showed a follower contact patch of about 4mm so obviously the followers are somewhat crowned and do not make full use of the lobe surface.

Since there is no significant pressure from valve springs I believe the cams should last a long time even tho they may show some mis-alignment.

Anyway.... Just gonna ride it!

Just as a side note, I rode a 1098 recently and was able to compare.
My 2006 999R has a bit less midrange and noticeably more top-end power. With pipes ( I've forgotten the diameter but they are the larger size, 62mm?) and chip from Corsa I think I am around 150 hp.

I made radical changes to suspension and geometry so it's not fair to compare handling but my initial impression was the 1098 steered like a truck!
All the Duc Superbikes are great but I have to say the 999 was a keeper!

Thanks to all and I report back in if something changes.

PS the Dunlop KR 449 slicks are GREAT and last a long time, I recommend them.

Fretka
 
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