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Yet another adjusting valves post....

2K views 14 replies 6 participants last post by  TAftonomos 
#1 · (Edited)
First swing up with a 4v motor, thank god it's a testta, looks to be loads more room for me, the noob, to figure this out.

Down to the question...

Measured the VC, here is what I got:

Right Side / Left Side

Intake opener .005" (006 fits/but TIGHT)/ Intake opener .005" (006 doesn't)
Intake loaded .011" / Intake loaded .011"

Closer = .006" / Closer = .006"

Exhaust Op .007" / Exhaust Op .008"
Ex loaded .012" / Exhaust loaded .013"

Ex Clo .005" / Ex Clo .005"


Bike was last serviced by ATL Triumph Ducati. This is 20K service at 11,600 miles. I read the specs are .007 open/.005 close, but I wanted to get your opinion on these measurements.

Both the intakes are dead on tied up, but unless they were set this way, how would the opener shims get tighter?

Is it ok to run the intake valves a bit tighter, as they should run cooler?

Finally, why is the measurement between rocker/cam a smidge different than the measurement rocker to shim? These above are rocker to shim, but it seems rocker to cam is a smidge bigger all around?



Thanks!
 
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#2 ·
Update, did the horizontal cylinder, cam/rocker measurements:

Intake LS / Intake RS
Opener .0055" / Opener .005"
Closer .005" / Closer .007"

Exhaust LS / Exhaust RS

Opener .008" / Opener .007"
Closer .008" / Closer .006"


Looks like I have to change at least 2 closers, so I might as well get them all down to a reasonable level (.004 ex / .005 in - per section8/others)

Fun Fun Fun....
 
#3 ·
New Ducati recommendations....

All closers (intake and exhaust) .002" - .004"
All openers (intake and exhaust) .004" - .006"

Old specs for FYI...

All valves, openers AND closers .004" - .009"

If I were you (and I am in your position as I'm putting my heads back on literally "as we speak" from doing my valve job) I would set all closers as close to .002 as you can get them. Closers get bigger with time and openers get smaller with time!! I would be fine with all your openers, but since they are super easy to fix, I'd tighten up the two exhaust openers a bit.

Same recommendation for the other head. What kind of bike is this???? It makes a difference and I'll tell you why when you answer...:)
 
#4 ·
2003 999, fun street bike.

Searching through this site and others it seems there are mixed feelings on the clearances. Ducati says 7-9 thou on the openers, and 5-7 thou on the closers, but others suggest as little as 2-3 thou.

Please tell what is the benifit of running them tight?

Also, since I'll be waiting on parts, I ought to go ahead and set up/check squish and degree the cams as well right? I just need to find desired cam specs on the 999 base motor. Also toying with the idea of throwing in some pistons while the jugs are off, but I'm not sure it's worth it for what the bike is/does.
 
#6 ·
You'll get away with excess clearance - no prob's, many Duc's chug along quite contently with a little excess clearance for many miles between clearance checks, and so long as it's not ridiculosly excessive you'll suffer little real world performance loss (this last bit is subjective!!).

You'll get away with that, no prob's - but DO NOT run clearances tight, or set them even a little tight, in the anticipation that over time they'll loosening up and give you extra time between checks - you bet they'll loosen up - quite possibly as broken valve seats and/or possibly as snapped valves - and the consequences thereof will not be pleasent (nor cheap)!

The best clearances? - those that the Ducati service manual gives as applicable for your model - or if aftermarket parts, possibly those as given by the manufacturer of those aftermarket parts (which are often the same as the Ducati clearances in any case - accept for some of the hardcore races parts)

Neil996r
 
#7 ·
Thats the thing Neal, how much is "excessive"? Ducati says 7-9 on the openers, 5-7 on the closers for a 999 (in the factory manual). Suggestions range from setting the closers to almost NOTHING, to 2-4. To me, 2 thou is more than twice as tight as 5 thou, and seems "excessive".

According to my factory specs, I'm tight on the openers on the intakes all around (I'm 0055" on 3/4) and loose on that one closer (.008" , ducati says 5-7)

If I need to re-set everything to make it a perfect 5 thou closer, 7 opener, I will.
 
#8 ·
TAftonomous, go back and re-read my post...Ducati has sent out a service bullitin or something, and new specs are .002"-.006" for all vavles, openers AND closers. They are recommending .002-.004 for closers and .004-.006 for openers. If you run your valves where they are now, you will most definately be fine and no danger of like blowing up or nothing. Look how long they've been running this motor with the old specs!! .002 is not too tight. Heck, look at the 2V motors...I run those at .000 - .001, with a MAX of .002. If I find a closer at .002 it's getting fixed. Did you read where I said closers get bigger and openers get smaller also??

Oldfart also made a great point about the shims since you have the half-ring retainers on your closers. I'd look into that if you have the money.

Checking squish involves pulling the heads...did you have them off anyways for some reason?? Just curious on that part!
 
#9 ·
"Please tell what is the benefit of running them tight?"
During normal use, the seats and valve faces gradually wear away causing the valves to recede into the chamber. This has the effect of loosening the closer clearance and tightening the openers. Any halfring wear or seating into the closer also loosens the closer adjustment. By biasing your adjustment as suggested, you are anticipating this normal wear.
 
#10 ·
headstud said:
"Please tell what is the benefit of running them tight?"
During normal use, the seats and valve faces gradually wear away causing the valves to recede into the chamber. This has the effect of loosening the closer clearance and tightening the openers. Any halfring wear or seating into the closer also loosens the closer adjustment. By biasing your adjustment as suggested, you are anticipating this normal wear.
Yes, you are correct and that is what I said...closers get looser. (I said bigger) Odds are, they are going to move between adjustments. How much, who knows????? Why would you not anticipate any wear?? ESPECIALLY with the standard half-ring retainers!!!! You're almost guaranteed a gain of .001 with half rings between checks. Benefit of running them tight?? I technically don't know why Ducati came out and changed the specs, but I know what makes sense to me...

If you have a closer that's say .008 (spec is .009 according to my factory manual) when you check it, are you going to leave it or adjust it??? Because if you leave it, time and wear are going to increase that number. It's going to get bigger like you said. Between my 6,000 mile check and just doing my 12,000 mile check, I had one closer increase by .004 (it went from .006 all the way to .010!!!), another increased by .003, and two others increased by .002. Why did they increase that much??? Who knows.

With tighter clearaces, specifically setting them at .002, you've got a lot more room for error IMO. If mine had been at .002 and had an increase of .004, the new .006 is still not too bad, still within specs, and definately not sloppy loose. Because me personally, I consider .010 on a valve sloppy and I'm not gonna run it that way. This is my educated guess why they changed the specs. Even if I'm off and this isn't why they changed it, it's still a pretty good feeling for me.
 
#11 ·
I'm interested in the date of the service bulletin for the Testastretta clearances being tightened up. Reason I ask, is that the opposite occurred on the Desmo motors - the 916/748/996 motors were all specified progressively looser over the years than previously.

My theory (a guess) is that the clearances tighten up when the motor is hot (easy to check, but I've never done it), and there is need for some oil film space.

It's a balancing act, as too large a clearance is also not good for the rockers/cams/valves, especially the rocker wear/chrome surfaces, as they don't like impacts caused by a fast accelerating cam ramp with excessive clearance.

I tend to set my valves at the one-third tight end range of the Ducati spec range (i.e. closer to the tight-end than the loose end), and try to avoid variances between the valves and cylinders of more than 0.001 between the related opener and closer, intake and exhaust clearances.
 
#12 ·
Makes good sense to me man. The last service was done a while ago time wise, and I'm sure they were using the origional specs for the testta.

I'll tighten the closers all up to 2-3 thou. Doesn't seem to hard to adjust them really.

If the openers are going to tighten up, I ought to shoot for 5-6 thou on those (better to loose than tight right - they will tighten up correct?)

NPR Ducati will sell me individual shims, and they are local to me, so it shouldn't be too long before I can get this thing back on the road.

Thanks for being patient with me, just learning :)

I have the tools needed to check the squish, and I'm curious to know what it is. A few people have said the newer motors are very close from the factory in both cam timing and squish, but there is no harm in checking it I suppose.
 
#13 ·
Old Baldy...I don't know the date nor did I see it myself. That being said...these new specs were confirmed and given to me by two sources...service manager at Modesto Ducati, and the service manager at Munroe Motors San Fransisco. Any Cali Ducati owner and probably a few others will confirm both of these as extremely reliable sources!! Interesting also is the fact I got the same story from two different sources. Besides that, I agree with everything you said...except I have a ZERO knowledge level on desmo motors:)

TAftonomous, yes, you read everything right...openers will tighten up with wear/use/age. You say you have the tools to check squish...why do you have your heads off anyways??

No problem and great questions...this is how we learn this stuff!!
 
#14 ·
galaxy said:
Old Baldy...I don't know the date nor did I see it myself. That being said...these new specs were confirmed and given to me by two sources...service manager at Modesto Ducati, and the service manager at Munroe Motors San Fransisco. Any Cali Ducati owner and probably a few others will confirm both of these as extremely reliable sources!!
and that's fair enough - the Testa motors are, after all, very different in the DVA mechanicc to the desmos. Just interesting that Ducati went in opposite directions with the 2 series, inn terms of gap specs.
 
#15 · (Edited)
galaxy said:
New Ducati recommendations....

All closers (intake and exhaust) .002" - .004"
All openers (intake and exhaust) .004" - .006"


If I were you (and I am in your position as I'm putting my heads back on literally "as we speak" from doing my valve job) I would set all closers as close to .002 as you can get them.
New specs so far, vertical cylinder

IL opener .0035" / IR opener .002" (I'll sand it out to .0035)
closer .0015" / closer .002"

EL opener .003" (I'll sand out to .0035) / ER opener .004"
closer .005" / closer .005"


I'm really confused as to what the closer are measureing out so far. I did install new half rings on all valves, and I added .03mm on both the exhaust closers, and only went from .0055 to .005. Should have snugged it up a thou, and then with the new half rings, another thou......guess my origional half rings wern't worn out then? Maybe my measuring sucks lol. I think I can move one over to make it work in the .002-.003 range, I'll go try now.

Since I'm waiting on a machined clutch basket, I might as well order another closers to take up the slack there.

Should I install old half rings on the IL closer to try and open it to .002? .002" will fit, but its a smidge draggy IMHO (maybe it's closer to .0017)


One more question....any chance there will be a noticable improvement over the way the bike runs, or any at all? :D


Shims that I need so far - 3.42 closer

I'm sure the horizontal cylinder is going to be fun, wish me luck lol.

Thanks again guys/gals!
 
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