Valve shimming for 2V. How often ?

[Duck-Stew]

So, how often do you change the collets? 

And, shouldn't one just buy MBP's and forget about the split rings forever?

I never change them.  Unless they're broken, they go back in.

MBP?  Nice stuff for sure, but I'm having good enough luck with the stock split rings.

[scott_araujo]

So, how often do you change the collets? 

And, shouldn't one just buy MBP's and forget about the split rings forever?

And further, you don't want to change them and you do want to install them same side down.  The collets seat a little when they are new.  This compresses them and leaves one side shinier than the other.  This contributes to your first service valve adjustment.  If you flip them, they reseat and you need to adjust your valves again.

If the MBP's are the ones I'm thinking of, yeah they're great, niced machined little beauties.  But I think they cost over $100 while the stock ones are a few dollars each.  Once the stockers seat they don't seem to change much. 

All of this is well detailed in the Desmo Times manual, including which way the shiny side goes on re-install and the MBP's.  It has nice things to say about the MBPs, after the first adjustment you're pretty well set it seems, they don't shift.  Nice stuff but a lot of money IMO. 

Scott

[bigiain]

Either 'new' or 'old' world specs, I find it odd that Ducati DOESN'T put the fact that the Desmo valves get better with age into any of their advertising...

I'm reasonably sure Ducati thinks anyone who keeps one of their bikes much past 20k is a pinko communist weirdo and don't want anything to do with them since they aren't about to buy the latest new model, and are just going to complain and whinge 'cause the parts they need aren't in stock locally...

big

[Jobu]

I never change them.  Unless they're broken, they go back in.

MBP?  Nice stuff for sure, but I'm having good enough luck with the stock split rings.

Hmmm, good to know.  Consider me the second member you've educated not to change the collets.  It seems I may have caused myself some work later on down the road, as my split rings were probably setup nicely.   

[Duck-Stew]

I'm reasonably sure Ducati thinks anyone who keeps one of their bikes much past 20k is a pinko communist weirdo and don't want anything to do with them since they aren't about to buy the latest new model, and are just going to complain and whinge 'cause the parts they need aren't in stock locally...

big

Right on my brother!  Power to the People!!!  [raises clenched fist]   

Hmmm, good to know.  Consider me the second member you've educated not to change the collets.  It seems I may have caused myself some work later on down the road, as my split rings were probably setup nicely.  

Just be sure you re-install them with the correct side down.  Otherwise, since you're wearing previously unworn areas of the split ring, it's like installing new ones...

[Gimpy]

I'm reasonably sure Ducati thinks anyone who keeps one of their bikes much past 20k is a pinko communist weirdo and don't want anything to do with them since they aren't about to buy the latest new model, and are just going to complain and whinge 'cause the parts they need aren't in stock locally...

big

Nice!!   I'm still in the middle of a weeks long valve service. I didn't know about the collets.  Thanks very much for bringing that up!  I am starting to think I need to buy the shim kit.  It's a lot of money, but I can't seem to figure out a process that will allow me to keep all the little things I need together.  I can do one valve at a time and go to the shop 8 times, or I can pull them all out and go once.  Any advice?

[Ddan]

You can pull them all, taking all your measurements first, and take lots of notes.  You may be able to swap shims between valves to get them in spec.  Figure what you need and take the old shims to the shop with you, some shops will exchange shims for less than the purchase price.  Make sure you bring your calipers with you, or have the shop measure your shims and get the new ones based on that measurement.  Do that for 3-4 yrs, get sick of the PITA and buy a shim set.       

[scott_araujo]

Nice!!   I'm still in the middle of a weeks long valve service. I didn't know about the collets.  Thanks very much for bringing that up!  I am starting to think I need to buy the shim kit.  It's a lot of money, but I can't seem to figure out a process that will allow me to keep all the little things I need together.  I can do one valve at a time and go to the shop 8 times, or I can pull them all out and go once.  Any advice?

Yes, measure each valve clearance and write it down.  Now measure both shims for that valve and write that down too.  Do this for every valve and write everything down.  Now do some math.  (These numbers are made up but you'll get the idea).  If your clearance is .03 and you want .02 and your shim is .12, you need a shim that is .13.  That .01 diff makes up the difference and gets you the clearance you want.  On the other hand, if your clearance was .01 you'd need a .11 shim.

If you write down all your clearances and all your shim measurements you'll be able to do two things:
1) See if you can swap some around so you have to buy fewer shims.
2) If after swapping you find everything is fine but a few shims are too big you can sand them down.

Some folks will tell you not to sand your shims since it removes the hardened top coating on the shim.  I've had no trouble doing this but the choice is yours.

If you want to sand down a shim you will need a flat surface, 600-800 grit wet sandpaper, and some light oil lubricant.  A marble tile is cheap and pretty flat, a shop table is not flat.  WD-40 works nicely as a lubricant.  Lay the sandpaper on the tile, spray some wd-40, and applying even pressure rub the flat surface of the shim in circles slowly sanding it.  Rotate the shim in your grip often to be sure you're getting a flat even surface and not creating a slanted surface.  Spray some more WD-40 often.  Measure very often, you don't want to go to far.  Wipe away the mess now and then.

Sand or don't, your choice.

Anyway, if you do all the measuring and all the swapping, you'll know how many shims you need and what size and since you opened every one for measuring you'll know if you have any broken collets to replace.  Then you can go buy them all at once.  You can measure in inches of mm but I think the stock shims are sold in mm.  Take your measuring tool to the dealer when you buy shims, measure them on the spot.  They may be labeled wrong and you don't want to have to drive all the way back after you install it and find that out.

On the other hand, I'm considering buying the shim kit too just to have everything right there.  I'm lazy   It's probably much cheaper to buy just what you need as you go and after a round or two you probably won't be adjusting that much.

Scott

[CMDRDAVE]

And further, you don't want to change them and you do want to install them same side down. 

This made me look at the receipt from the last valve adjust.  "Replaced all valve retainers/half rings"     I was hoping i wouldn't have much to adjust when I try myself in a month.

[scott_araujo]

How much did that cost?  Finding one or two broken is not uncommon, all of them is.  Are they just padding the bill?

Scott

[Duck-Stew]

How much did that cost?  Finding one or two broken is not uncommon, all of them is.  Are they just padding the bill?

Scott

The 7mm rings are much more common to break, the 8mm...not so much.

[pitbull]

I've got around 240,000km on my 99 M750, and I haven't changed a shim in over 100,000km. I changed all of them to "old school" specs at the 80,000km service (this first one I did myself), then needed the tweak two shims sometime after that, and have just checked them every 10,000km ever since (I think a couple of closers are probably a little looser than I'd set them if I was gonna go in and change any, but not as loose as the "new world" spec...)

big

I gotta say.......that's some impressive mileage. I thought I was doing well with 100,000 km on my 2001 900, but wow......very nice.

[ducpainter]

The 7mm rings are much more common to break, the 8mm...not so much.

Tell my monster that...

[Duck-Stew]

Tell my monster that...

Ok, ok...  They're not unbreakable, just much less likely IME.  On a 4V desmoquattro, if you're doing the valves and don't have to replace at least 1 or 2, you got lucky.  On a 2V, I'd see a broken one about every fourth or fifth valve adjustment.  That's been my experience...your Monster may have other issues DP...

[ducpainter]

Ok, ok...  They're not unbreakable, just much less likely IME.  On a 4V desmoquattro, if you're doing the valves and don't have to replace at least 1 or 2, you got lucky.  On a 2V, I'd see a broken one about every fourth or fifth valve adjustment.  That's been my experience...your Monster may have other issues DP...

My Monster has had at least one broken every 6K....or every couple of years if I was low mileing.

The clearances are set old world...and always have been.

I ran without a tach for a long time and hoped that not constantly revving the snot out of it would help.

I think it has one major issue...

loose nut in the seat.