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another valve adjustment question

Started by SeaLander, February 20, 2010, 04:30:52 PM

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ducpainter

#15
March 21, 2010, 06:32:11 PM
Quote from: WarrenJ on March 21, 2010, 06:14:42 PM
Just did my first valve job on a 2000 750 with 7000 miles on it.  Openers were all tight and were readjusted to .004 and closers were fine.  One thing I noted, at least on the horizontal cylinder was that the opener and closer dimensions changed between having the belt on or not.  Is this usual or is it indicitave of another issue?  I've put 300 miles on it this week and it is running smooth and strong so at least emprically, its working....
The only causes could be that the belt was slightly rotating the cam...

or the cam bearings are worn and the taught belt is pulling the cam closer to the rockers.

How much different?
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 perspective
    is even more amazing than yours."
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WarrenJ

#16
March 22, 2010, 04:31:43 AM
About .002 - I went with the dimensions with the belt on as this is the operating condition.  In that condition, I had .004 on the openers and .0055 - .006 with the rocker depressed - delta of .0015 to .002
This isn't a dress rehearsal for life - this is it!

ducpainter

#17
March 22, 2010, 04:34:23 AM
Quote from: WarrenJ on March 22, 2010, 04:31:43 AM
About .002 - I went with the dimensions with the belt on as this is the operating condition.  In that condition, I had .004 on the openers and .0055 - .006 with the rocker depressed - delta of .0015 to .002
I'd pull the belt and check for movement of the cam I think. I've never heard anyone else say the numbers changed from installing the belt.

I think your closers are a bit loose.
"Once you accept that a child on the autistic spectrum experiences the world in
 a completely different way than you, you will be open to understand how that
 perspective
    is even more amazing than yours."
    To realize the value of nine  months:
    Ask a mother who gave birth to a stillborn.
"Don't piss off old people The older we get, the less 'Life in Prison' is a deterrent."


WarrenJ

#18
March 22, 2010, 04:38:00 AM
The couple of sources I looked at for dimensions recommended .002  - what is your recommendation?
This isn't a dress rehearsal for life - this is it!

ducpainter

#19
March 22, 2010, 04:41:03 AM
Quote from: WarrenJ on March 22, 2010, 04:38:00 AM
The couple of sources I looked at for dimensions recommended .002  - what is your recommendation?

That would be a max. dimension according to Ducatis new specs.

As close to zero as possible without any binding of the cam.
"Once you accept that a child on the autistic spectrum experiences the world in
 a completely different way than you, you will be open to understand how that
 perspective
    is even more amazing than yours."
    To realize the value of nine  months:
    Ask a mother who gave birth to a stillborn.
"Don't piss off old people The older we get, the less 'Life in Prison' is a deterrent."


WarrenJ

#20
March 22, 2010, 04:45:36 AM
Is this "new spec" for newer bikes or is it an updated spec for all monsters?
This isn't a dress rehearsal for life - this is it!

ducpainter

#21
March 22, 2010, 04:51:33 AM
Quote from: WarrenJ on March 22, 2010, 04:45:36 AM
Is this "new spec" for newer bikes or is it an updated spec for all monsters?
It is a spec that Ducati published to reduce maintenance costs. It started in '05 or '06 with no real changes to the bikes when all of a sudden a bike could now go 7500 miles between adjustments instead of 6K.

You decide which numbers you want to use.

The consensus seems to be that a 2V Duc will run better with the tighter tolerances.
"Once you accept that a child on the autistic spectrum experiences the world in
 a completely different way than you, you will be open to understand how that
 perspective
    is even more amazing than yours."
    To realize the value of nine  months:
    Ask a mother who gave birth to a stillborn.
"Don't piss off old people The older we get, the less 'Life in Prison' is a deterrent."


WarrenJ

#22
March 22, 2010, 05:07:19 AM
What changes as the clearance is reduced to zero?  I'm new to working much on internal combustion engines so please bear with me - I'm trying to conceptualize the relationships of the parts I just worked on and the causes and effects of the changes I made. 
This isn't a dress rehearsal for life - this is it!

ducpainter

#23
March 22, 2010, 05:13:55 AM
Quote from: WarrenJ on March 22, 2010, 05:07:19 AM
What changes as the clearance is reduced to zero?  I'm new to working much on internal combustion engines so please bear with me - I'm trying to conceptualize the relationships of the parts I just worked on and the causes and effects of the changes I made. 
The effect of the forces on the keepers, or collets, for one. Loose closers and high rpms can break the collets. The valve also closes slightly later with increased clearance. So you are in effect altering the cam timing. A loose, or tight belt, will do the same.

We should probably stop jacking this thread... :-[
"Once you accept that a child on the autistic spectrum experiences the world in
 a completely different way than you, you will be open to understand how that
 perspective
    is even more amazing than yours."
    To realize the value of nine  months:
    Ask a mother who gave birth to a stillborn.
"Don't piss off old people The older we get, the less 'Life in Prison' is a deterrent."


Armor

#24
March 22, 2010, 07:48:20 AM
Ducati changing the Minimum clearance from <.001 to .002" has NOthing to do with longer service intervals.  Think about it.  Changing the max clearance will extend the service intervals.
04 M1000s, Arrows, Light Flywheel, Ohlins suspension

ducpainter

#25
March 22, 2010, 03:05:44 PM
Quote from: Armor on March 22, 2010, 07:48:20 AM
Ducati changing the Minimum clearance from <.001 to .002" has NOthing to do with longer service intervals.  Think about it.  Changing the max clearance will extend the service intervals.
So longer service intervals and extended intervals are different...

how?

Seriously are you a Ducati employee? ???
"Once you accept that a child on the autistic spectrum experiences the world in
 a completely different way than you, you will be open to understand how that
 perspective
    is even more amazing than yours."
    To realize the value of nine  months:
    Ask a mother who gave birth to a stillborn.
"Don't piss off old people The older we get, the less 'Life in Prison' is a deterrent."


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