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Discussion Starter · #1 ·
I was in the process of replacing the fuel tank on my hyper due to it developing a hole in it where the battery sits and decided to knock out the valve clearance checks since I'm only 1k miles from the recommended interval. (every 7500) Bike currently has 14k miles on it.

The first thing I see after pulling the first valve cover off on the vertical head is the split rings that hold the closer shim in place are in four pieces. Great! I checked all the clearances and as expected, the closers are all too loose and openers mostly a bit tight. I'll include numbers if anyone would like to give me some input. Ideally I'd like to get the closers to .000" (belts off spinning cams to verify no binding) and openers on intakes to .004" and exhaust openers to .006"

The part I really would like some advise on is replacing the half rings. The measured clearance before I replaced the half rings was .006" and .003" after. I was surprised to see I gained a few thousands just by changing the split rings. If my thinking is correct, I can now go ahead and still tighten this up more, knowing that the new rings will set in and cause that clearance to open up, correct? Shims are only in .05mm/.002" increments so the
best I could do is .001" for that closer. Now I'm contemplating if I should just replace all 4 sets of split rings and remeasure my clearances. Is this a good idea or does everyone prefer to leave these rings that are already set in? Most of my closers are at .005" or .006" so I could replace the split rings and re-shim, or just re-shim and leave the good split rings?

Heres my valve specs:

HORIZONTAL
Exhaust Valve
Opener: .003"
Closer: .005"

Intake Valve
Opener: .001"
Closer: .006"

VERTICAL
Exhaust Valve
Opener: .003"
Closer: .004"

Intake Valve
Opener: .004" (.003" after replacing broken half rings)
Closer: .006" (.003" after replacing broken half rings)

Thanks for the help!
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the collets (split rings) do bed in, so next time it comes apart you'll have to adjust closers again because of that. just how it is. i only replace when they're broken or very worn.
 

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I've seen this happen before on my bikes I attribute it to openers getting tight from exaust valve seats pounding deeper in the head & valve face wear...witch is normal to happen on any engine with aluminum heads.

My question is does anybody make a better quality closer ring? I'd really like to replace all of mine before a broken one decides to fall out possibly dropping a valve or just about as bad loosing a chunk of ring into my bottom end eventually finding its way into my gearbox before it gets sucked into the primary oil pump pickup screen to be discovered @ next oil change.
 

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Discussion Starter · #4 ·
I've seen this happen before on my bikes I attribute it to openers getting tight from exaust valve seats pounding deeper in the head & valve face wear...witch is normal to happen on any engine with aluminum heads.

My question is does anybody make a better quality closer ring? I'd really like to replace all of mine before a broken one decides to fall out possibly dropping a valve or just about as bad loosing a chunk of ring into my bottom end eventually finding its way into my gearbox before it gets sucked into the primary oil pump pickup screen to be discovered @ next oil change.
There are these aftermarket collets that take the place of the stock split rings. They do have great reviews and guys talk about not having to replace a closer shim 15k miles after installing these. I’ve heard they are more an interference and harder to get off but might be worth it.
 

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Discussion Starter · #5 ·
the collets (split rings) do bed in, so next time it comes apart you'll have to adjust closers again because of that. just how it is. i only replace when they're broken or very worn.
Besides being broken in 4 pieces, what does a really worn split ring look like? All the other ones look like new.?
 

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Besides being broken in 4 pieces, what does a really worn split ring look like? All the other ones look like new.?
They generally have a brighter/shiny appearance on one side, which doesn’t necessarily mean they’re no good, but it pays to pay attention to which way they were oriented and put them back the same way or they will bed in again. I have no idea what could cause yours to break in 4 pieces.
 

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I have checked my broken ones against non broken with a hardness tester & found the busted ones Rockwell C 30 & non broken C 22

The broken ones are too hard & brittle & I have no idea what spec is supposed to be, I do know that you grab them with two pair of pliers & twist some break & some don't they bend

Ahhh quality control at its finest!
 

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that's interesting. usually they break on 4v that get revved hard. i see a few ds style 2v engines break them on inlets. filing the burr off before you fit them helps.

i've never had bits missing, they're always there.
 
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