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Nope, they're a real bugger to get to on the Scrambler, it's very compact! Plus I don't have a big box of shims and can't be arsed to get them posted ;-) I've rebuilt motors before where I've dropped the heads in to a local indie to be reshimmed. Earlier heads need a factory tool, not sure about these though.
 

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I'll be doing mine. I've done the valves on loads of Ducatis before, both 2V and 4V, and don't see it as a problem.
 

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Discussion Starter #4
That's good to hear, Derek. We've generally tended to the valves on other bikes, some with shims, but mostly screw and lock nut. I hope to tackle this, but have to say I'm spooked. Are these particular shims Ducati only? I figure so. Thanks again.

Sarah
 

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It's not a difficult process Sarah. The shims are indeed Ducati specific. The openers are easy to access and change, the closers much less so, but if you are patient and take your time to understand how the system works most average mechanics should have little difficulty. Always measure 3 times to be sure you don't get a spurious reading.
 

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Discussion Starter #12
Thanks, thanks, everybody. I've got the fuel line disconnect tool from Motowheels on the way, there's step one. Thanks for the guide Derek, I'll start studying. More questions to come, for sure. First off, we've always found TDC by bumping the rear wheel, that OK for this bike, I reckon? Thanks again.

Sarah
 

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Sarah,

I plan to do the valves too. Used to do them on my old BMW R90s in about a half hour. This bike will probably take a couple days if shims are needed and not on hand

Some good info here

ducatitech.com - chris kelley's ducati information site
Guide to adjusting Desmo valves.

Bunch of videos on YouTube. While old, the 2 valve videos are probably spot on for this motor. Have to verify the clearance specs to be sure though

ducatitech - YouTube

Seems pretty straightforward but the videos show the motor on the bench which is way easier to access than when mounted.

Shim kits here.

Standard Shim Kits | Product Categories | EMSDUC

I have seen the C-clips mentioned elsewhere. Apparently they wear into place and if re-used the next adjustment won't come as quickly. I have no direct experience but it makes sense that if they wear a bit early on but not much after that then you basically fix the C-clip wear with a new shim to make up the difference. Conversely, as one of the other contributors mentions, if you replace the C-clip then you may not need a shim.

It appears the closing shims have to be the most precise which makes sense. You don't want the cam follower to bottom out or have a lot of lash. Some of the shim info says that you can lap them into tolerance if slightly too big. But it seems some are only case hardened and you can lap thru the hard layer so picking thru hardened shims may make sense.

Another point they all make is to get plastic forecepts and notch it to hold the valve stem when the closing shim is out so the valve doesn't drop in. I expect a backup is to make damn sure the piston is at TDC which may prevent it from falling all the way in.

My first time will be slow and steady but there appears to be no magic to it. Just very different from other systems.

Good luck

Phil
 

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Another point they all make is to get plastic forecepts and notch it to hold the valve stem when the closing shim is out so the valve doesn't drop in. I expect a backup is to make damn sure the piston is at TDC which may prevent it from falling all the way in.
Always have the head you are working on with the piston at TDC. With the piston at the top the valve can only drop about 5mm or so but it needs to be held fully closed to allow the closer down far enough to remove and replace the half-rings. Forceps are certainly a big help.
 

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Discussion Starter #16
We're old hats with the airheads too Phil, different for sure. C-clips vs shims, have to study on that one, right off the bat makes you want to lean toward replacing clips if that would save fooling with shims. I've got a pile of reading and studying to do. Thanks so much for the links, and you all please keep the info coming.

Sarah
 

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Discussion Starter #17 (Edited)
Finally got the tank off:

Tips on Tank Removal

Now to tackle the valves. Fair warning, it takes a good amount of work just to get to the valve covers. We're just getting started, but on the front cylinder it looks like we've got tight openers and loose closers at 9000 miles. (Let me add that this is our first Ducati, so take anything I post with a grain of salt, it may be that we just don't have a clue.) I've been reading that the c-clips wear early on bringing the valves out of adjustment; once they work-harden they become stable, allowing the valve tolerances to remain more stable, too. Does this sound right? If it comes to needing shims, do you all use OEM, or do you prefer EMS shims? Please chime in, any insights much appreciated, thanks.

Edit: Whoops, Phillip clarified the C-clip issue several days ago. Does it make sense to leave these C-clips alone and address the shims?

Sarah
 

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Finally got the tank off:

Tips on Tank Removal

Now to tackle the valves. Fair warning, it takes a good amount of work just to get to the valve covers. We're just getting started, but on the front cylinder it looks like we've got tight openers and loose closers at 9000 miles. (Let me add that this is our first Ducati, so take anything I post with a grain of salt, it may be that we just don't have a clue.) I've been reading that the c-clips wear early on bringing the valves out of adjustment; once they work-harden they become stable, allowing the valve tolerances to remain more stable, too. Does this sound right? If it comes to needing shims, do you all use OEM, or do you prefer EMS shims? Please chime in, any insights much appreciated, thanks.

Edit: Whoops, Phillip clarified the C-clip issue several days ago. Does it make sense to leave these C-clips alone and address the shims?

Sarah
Tight openers and loose closers is what I'd expect now that the seats have bedded down. Many people find that changing the half-rings (C-clips) brings the clearances back within spec but new half-rings haven't work hardened and may bed down quite quickly making the clearances loose again. However, if you decide to retain the existing half-rings you may find that quite a number of closers need changing although it's often possible to swap between different valves, if you are lucky, cutting down the number of shims you need to order.
I've always used OEM shims, simply for convenience as I can have them by the next day, day after at most.
 

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Hello

On my ST2, when checking the valve clearance, I proceeded as such, for each valve :
- I check the opening and closing clearances, if they are in the right interval, do nothing, re-mount everything and drink a beer :)
- when a clearance is out of the right interval, change the C-ring
- re-check the clearances, after having made 2 or 3 engine turns (by hand), so everything goes back in place
- if they are back in the right interval, stop here and drink a beer :)
- if they are still out of the interval, calculate which value you need for the shim for this valve
- if you need a really near and lower value, try to wear it on a 600 sandpaper, on a flat surface (a mirror, for ex.)
- if you need a larger value, request it from your dealer and propose him to exchange it with yours

Just remember the piston must be on the high neutral point. If not, the clearances are false. There is a different mark for each cylinder on the alternator. So, check you're measuring the clearance on the right cylinder according to each mark.

Last but not least, the closure clearance needs to be measured with someone who pushes strongly down on one side of the rocker, while you measure the clearance on the other side. If not, your measure will be false, you'll find no clearance, which is abnormal.

May this help...
 

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Discussion Starter #20
I've been on the phone with the parts dept at three area dealers (nearest 100 miles away) and decided to order a shim kit from EMSDUC, as Phil suggested. I'll keep you posted, and thanks again for the help.

Sarah
 
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