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View Full Version : Guide: Valve Clearances, Shims and Seals. (Pic Heavy)


Macflurry
02-09-2018, 11:41 PM
Hi guys, thought I'd try and give a little back to the community as a new member. I've had problems with oil ending up on my spark plugs so before going to the extent of stripping out the heads and swapping out o-rings and piston rings I thought that I would start by ruling out the easy options first. So while going in to change the valve stem oil seals it gave me a chance to go through checking the valve clearances and also to measure up the shims for replacements if needed. Now, in reading up online I found an abundance of information with a million different ways to achieve the same end results but what I did notice was that everything I was after was scattered across several places or didn't quite answer my questions. So I've tried to put together all the info that I found useful as I went through the work. I've tried to keep it as comprehensive as possible and aimed it at someone like myself who was going in from scratch knowing nothing, but anything that I've missed or anything that you guys find wrong then please let me know and I'll happily get it changed to make it accurate for members to use in future.

Before I get started I want to point out that this isn't only my first Ducati, it's my first bike too. I've only had it a couple of months and I'm going in at the deep end. I've had it out on the road three times and already stripped, re-jetted and rebuilt the carbs, then swapped the seals and looked at the clearances, and from here I'm going onto removing the heads... so if this post goes well then that one may follow. As I am new to working on bikes then some of the seasoned pro's on here may cringe at how I go about some of this but, again, it's a learning curve. Tell me what I've done wrong and I'll happily get it changed out to improve the thread.

This thread will be pretty big so I've reserved the first few posts to break it up and I'll build it up over the next few days. This will be a work in progress for a while but bear with me and hopefully it'll be a worthwhile guide.

The thread will be broken down as follows:

1. Desmo’, how it works.
2. Checking valve clearances.
3. Removing/refitting shims
4. Measuring shims.
5. Swapping out valve seals.
6. Additional Info
7. Remarks

*** Usual disclaimer: The info contained in this thread is what I have pieced together to use on my own bike. I am very definitely not a mechanic. Use this information at your own risk as it worked for me but may not gO so well for you. I am not responsible for the work you carry out on your own bike. Do your own research, find your own sources, put together your own plan that you're happy with and if in any doubt ASK A PROFESSIONAL!! ***

Cheers guys, enjoy the thread. :thumbsup:

Macflurry
02-09-2018, 11:42 PM
1. Desmo’, how it works.

Understanding how the demo’ system works and what it does helps to understand what you are checking and why with your valve clearances and then also what you are trying to achieve by adjusting them.

I said earlier I would try to cater for everyone from the ground up, so...

Engine basics - The four stoke engine works using the phases shown in the picture below.

https://tinyurl.com/y7nfaqce
Image from http://web.mit.edu

1. The intake stroke opens the inlet valve and draws in the air/fuel mixture on the pistons down stroke.
2. The compression stroke closes the valves and seals the chamber to build up pressure on the pistons up stroke.
3. Spark ignites the air/fuel mixture and the combustion forces the piston down.
4. The pistons down stroke is called the power stroke as the downward force from the combustion creates the power that turns the engine over.
5. At the end of the power stroke the exhaust valve opens for the exhaust stroke allowing the piston to force the exhaust gas out past the valve. At the end of the exhaust stroke the exhaust valve closes and the cycle starts again.

This is a very loose description of its operation but you get the idea.

Traditionally most bike engines work by using the camshafts in the cylinder head to push open the inlet and exhaust valves, when required throughout the phases of the cycle, using rockers. Then, as the cams rotate past the rockers, springs are used to force the valves closed. But, the springs take time to kick in and force the valves closed. Enter the desmodromic system...

Over the years Ducati have developed the desmo’ system which uses cams and rockers to open the inlet valves, as above, but also uses a second set of cams and rockers to mechanically close the valve when required instead of relying on the springs.

https://tinyurl.com/yaxk65gz
Image from http://www.ducati.com

The image above is taken from Ducatis website and shows the components of the desmo’ system. The blue camshaft at the top centre runs through the heads and has a cam for each of the rockers. The two red rockers at the top left and top right control the openers. As the arm in the centre is pushed up by the cam the arm at the opposite end pushes down on the opener shim on the top of the valve, in yellow, and forces the valve open. As the cams turn further the opener is released and the closer cams press on the rocker arms, at the bottom centre, causing the opposite end to push against the closer shim and force the valve closed. This process then repeats throughout the combustion cycle.

Ducatidesmo.com have produced an animation that clearly shows the operation of the desmo’ system using cams to force the valve open and closed.

http://ducatidesmo.com/images/ducatidesmovalves.gif
Image from http://ducatidesmo.com

When the system is set up properly the cam should hold the rocker arm as flush to the closer shim as possible as it passes so that the cam seals the valve to its seat as best it can but not so tight that it causes binding. A gap is left between the opener arm and the opener shim to ensure that the valve isn't inadvertently keep the valve forced open when it isn't required to be. Over time, as the valve repeatedly hits the seat as it closes it will bed itself further into the head causing the gap to increase between the rocker arm and the closer shim and also the gap to decrease between the rocker arm and the opener shim. On Ducatis picture above you will notice a spring, again in yellow, attached to each of the closing rockers. This is to take up the last of the slack on starting and idle to ensure that the valve fully closes at low speeds if the closer gap gets bigger.

Macflurry
02-09-2018, 11:43 PM
2. Checking valve clearances.

The factory spec's for the valve clearances, taken from Ducati Monster 900 Workshop Manual, are as follows:

2v engines.

Opening Rocker

Inlet, mm/in. 0.10-0.12/0.0039-0.0047
Exhaust, mm/in. 0.12-0.15/0.0047-0.0059

Closing Rocker

Inlet and exhaust, mm/in. 0.03-0.05/0.0012-0.0019

4v engines have different recommended clearances.

Before measuring any of your own clearances ensure that the engine is as cold as possible, ideally left overnight!!

When you read around there are various alternative measurements that are offered up, each for their own reasons to the person who uses them. The following table has been put together to show the various settings from sources ranging from manufacturer, professional engineers, enthusiasts and magazine articles. From here you need to read around and decide whose methods suit you best for your application. There’s no right or wrong answer just different opinions on how to approach the adjustments. But from what I’ve read across them all a sensible approach is to not aim for the smallest reading possible.

Closers: Ideally under 0.001” but not so tight that it binds although anything up to 0.002” is good.

Openers: Ideally aim to adjust for 0.004” or very slightly over.
If in doubt call a Ducati specialist for advice.

Online recommended Settings

https://tinyurl.com/y7hg9vut

Carrying out the valve checks.

1. Before you start put the bike into its highest gear so you can turn the engine over using the rear wheel and put it up on a stand. Tools are available to turn the engine over by hand but they can be pricey from Ducati.

2. If you are working on the vertical cylinder then you need to remove the seat, the tank, the battery and battery tray to make as much space as possible around the cylinder head.

If you are working on the horizontal cylinder head then the bolts securing the oil cooler need to be removed along with the bolt for the oil feed to the carb’s so that the cooler can be lowered out of the way. I also had to remove the mud guard to get the cooler fully out of the way.

3. Once you have sufficient access to the cylinder head remove the four bolts on each of the inspection covers to expose the valves, rockers and shims. This also allows you to view the rockers and see the valve states as the engine is rotated.

https://tinyurl.com/yak9arvx

4. Remove the spark plugs and then using the rear wheel, turn the engine over by hand until you line up the arrow marker in the bottom left with these lower of the two marks on the side of the flywheel through the inspection window.

https://tinyurl.com/yb2epms5

5. Now that you’ve found top dead centre (TDC) the question is which one? The horizontal and vertical cylinders both reach TDC at different times. Every time the flywheel passes through this marker one of the cylinders reaches the top of its cycle. The easy way to tell which has reached the top is by sliding a screw driver into the spark plug hole and checking which one hits a piston. Another way is to remove the top belt cover on the back of the vertical cylinder and check where the pulley marker is. If the indentation on the pulley is lined up with the plastic mark on the casing to the left then the horizontal cylinder is at TDC. If the pulley marker is at the 4 o’clock position then the vertical cylinder has reached TDC.

https://tinyurl.com/ybb48dswhttps://tinyurl.com/ybk6phcg

Macflurry
02-09-2018, 11:43 PM
6. Working on the cylinder at TDC you will next check the opener and closer clearances. At TDC both valves should be closed meaning that there should be no pressure on the opening rocker, and so there should be a gap between the rocker and the shim, as well as the cam having pressed the closer rocker shut which should leave virtually no gap between the rocker and the shim. There is more than one way to check clearances but here we will check them using the unloaded and loaded gap.

The unloaded gap is when measurements are taken with no pressure on the closer rocker and the loaded gap is where measurements are taken with pressure is applied to the closer rocker as follows.

7. Unloaded gap.

With the valve in the closed position, at TDC, leaves no pressure on the opening rocker, the unloaded gap between the opener shim and the rocker is measured as the opener clearance and the values noted and compared to the clearance requirements.

The right feeler gauge should slide all the way through the gap without force and has been likened to sliding the feeler gauge through a thick book. If the feeler is too big then there is too much pressure required, the gauge will snag and will need to be forced through.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Checking%20Clearance/Checking%20Valve%20Clearances%2005.jpg

8. Loaded gap.

Still with the valves in the closed position, at TDC, the gap between the cam and the closer rocker, and then the rocker and the closer shim, should be at a minimum. As wear and tear increases these gaps the slack is taken up by the closer spring to fully seal the valve. If the closer rocker is pressed down with a screwdriver you can feel the rocker move through the gap that has grown. To measure the closer clearance, remeasure the opener gap, as in the previous step, but with a screwdriver pressing down on the closer rocker and note the value. This gap will now be bigger than before. To find the closer clearance simply subtract the value previously found for the opener clearance from the loaded gap measurement. The figure that’s left is your closer clearance.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Checking%20Clearance/Checking%20Valve%20Clearances%2006.jpg

9. Note down all measurements, opener and closer clearances for the inlet and exhaust valves on the horizontal and vertical cylinder heads, so 8 measurements in all. Check these against the clearance spec’s you wanted at the start and decide which shims, if any, you need to adjust to bring the clearances back into spec’. To work out the new shims needed you need to measure the old ones and add or subtract the amount the clearances were out of spec’.

Macflurry
02-09-2018, 11:44 PM
3. Removing Shims.

1. To adjust the clearances, you need to remove the old shims and measure them to calculate the new sizes. First up block the oil drain in the bottom left of the picture with an allen key or an ear plug to stop anything that you’re working on dropping down. Then pry the black retaining clip in the top right off. Be careful as these can go flying across the room.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Removing%20Shims/Removing%20Shims%2001.jpg

2. With the retaining clip removed the opener rocker arm can be slid to the side. I found that to do this I had press the closer rocker and valve down out of the way. To press the closer and valve down further I had to move the cam pulley to just before or just after TDC depending on which valve I was working on. With the valve out of the way the opener rocker can drop slightly and move to the side exposing the opener shim. The opener shim can now be pulled off from the valve.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Removing%20Shims/Removing%20Shims%2002.jpg

3. To remove the closer shim the closer rocker needs to be pressed all the way down so that the closer shim can be slid down the valve and the retaining collets can be removed. To press the closer rocker down the cams must be rotated to before or after TDC. But BEWARE, once the collets are removed there is nothing to stop the valve falling into the cylinder. One method I heard to prevent this was to fill the cylinder/head with rope through the spark plug hole, another was to use a long zip tie around the stem and weight the end of the tie with mole grips so the weight stops it falling and a third way that I read was to use forceps to grip the valve. I had a go with all three.

a. The rope worked but I was always wary that I hadn’t filled it enough, that as I worked the rope may shift and that I may be leaving debris in the cylinder. When you turn the engine back to TDC to compress the rope against the head it may compress and move too far so you cant depress the rocker as far as you need to remove the collets. So it’s a balancing act.

b. If you zip tie the top of the valve to remove the collets you then need to use another zip tie at the base before cutting the first off to remove the shim. If you just go for zip tying the base it may get in the way of the rocker depending on the size of the ties that you have. You also need to ensure that they are ratcheted right up as the valve can slip through the loop if you’re not careful, or put a slim piece of electrical/self amalgamating tape around the valve for the tie to bed into. That should help with slipping. Instead of mole grips as weight I also tried attaching the zip tie to the opposite rocker, with another zip tie, to hold the valve up.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Removing%20Shims/Removing%20Shims%2003.jpg

c. I ended up going with the forceps method but it isn’t without flaws. I used two sets in the same places the zip ties were tried and they are quick and easy to switch between the two but they can be slippery so you need to double check they are locked and gripping before removing the second set. I wrapped self amalgamating tape around the tips and also cut half of the loop tip off to make them smaller to work around. If I was feeling paranoid about how well one was ripping I used a Velcro tie around the ratchet to stop it popping open.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Removing%20Shims/Removing%20Shims%2004.jpg

Macflurry
02-09-2018, 11:45 PM
4. My multitasking skills weren’t up to scratch to take pics for the next part so you’ll have to make do with an alternate pic. With your valve secured and cams moved away from the TDC point you are ready to press the closer rocker down and slide the closer shim down the valve stem exposing the collets. Working out how far to move the cams/pulley was a lot easier with the head off as you can twist it until it stops on its own just before the opposite valve would be about to open. When doing it with the back wheel it’s a bit more of a guessing game as to how far you’ve gone. With the collets exposed a magnet will easily whip them out safely and reduce your chances of dropping them down the oil drain… you did plug that up right??

The image below shows the shim and collet removed but you can see that it’s a pretty big groove that you’re looking to completely expose so you’ll definitely know when the shim has moved out of the way enough. The face of the rocker either side of the groove can be pushed all the way to the bottom leaving plenty of room to remove the collets but the problem you will have is not having enough hands!! The difficulty comes with pressing the rocker down without slipping, sliding the shim down without moving the valve down, grabbing the magnet to get the collets out and also moving the collets around the groove if you cant get to the one at the back. Go slow, have patience. Don’t put a screwdriver on the shim, it’s bad enough using one on the back of the rocker, the lip is small and will be guaranteed to slip off and damage something like your valve stem seal or worse your hand (done it, not as fun as it sounds)!!

With the collets removed the shim can be slid up and off of the valve. For peace of mind at this point spin your wheel so the cylinder is back to TDC. In the event that something disturbs your zip ties or calipers you won’t lose the valve into the cylinder. I’d recommend doing them one by one so you don’t accidentally mix up parts as they are measured and refit.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Removing%20Shims/Removing%20Shims%2005.jpg

Refitting.

1. Once your new shims arrive then refitting is the opposite of the removal process. But are a couple of points to note:

a. Collets – indentation. If you are reusing your collets then you will notice that over time a groove has been made into the inside of the collets one side. When refitting this should be on the top side of the collets as it was caused from being repeatedly pressed against the corner of the valves groove by the rocker and the shim. The picture below shows the groove worn into the top on the left collet and the round bottom on the right collet. Unfortunately zoomed aren’t the greatest quality ut hopefully it still works for you.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Measuring%20Shims/Refitting%20Shims%2001.jpg

b. When the opener rocker is slid back into place, over the opener shim, ensure that a metal washer sits either side of the gap before refitting the black retaining clip. On the picture below, you can just make them out either side of the fitted clip.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Measuring%20Shims/Refitting%20Shims%2002.jpg

c. Finally, remember to remove what ever you used to block the oil drains!!!

Macflurry
02-09-2018, 11:46 PM
4. Measuring Shims.

1. With the shims and collets removed from a valve you should ideally also have the measuring tools to accurately check which size shims you have (Picture below, left to right: opener shim, opener shim measuring tool, closer shim measuring tool, closer shim and bottom centre are the collets). The measuring tools are simply two adapters that slot into the shims. You simply:

a. Measure the tools and note the size. Each tool needs to be measured across specific points, which will be covered later, and not always the very top to the bottom.

b. Slot them into the relevant shim, measure both together and note the size.

c. The tools fit in and touch the point where the valve would make contact. Subtract the size of the tool from the total of both and what you have left is the size of the shim from the face to where it touches the valve.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Measuring%20Shims/Measuring%20Shims%2001.jpg

2. Opener shim: The tool for the opener is simply measured from top to bottom as shown below. This measurement is then subtracted from the measurement of both the tool and the shim slotted together, also below. The result is the thickness or size of the shim.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Measuring%20Shims/Measuring%20Shims%2002.jpghttp://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Measuring%20Shims/Measuring%20Shims%2003.jpg

3. Closer shim: The tool for the opener is not measured from top to bottom but from the shoulder to the bottom as shown below. The top of the tool sits in the hole the valve would go through and touches nothing but the shoulder sits where the collets make contact. This measurement is then subtracted from the measurement of both the tool and the shim slotted together, also below. The result is the thickness or size of the shim.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Measuring%20Shims/Measuring%20Shims%2004.jpghttp://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Measuring%20Shims/Measuring%20Shims%2005.jpg

4. Move through all of your shims that required adjustment after measuring your clearances. To work out your new shim sizes, take the amount the clearances were out of spec’ by and if the gap was too big then add it to the shim size to reduce the gap. If the gap was too small then subtract it from the shim size to make the gap bigger.

Macflurry
02-09-2018, 11:46 PM
5. Swapping Out Valve Seals.

1. Follow the steps above as far as removing the closer shim, clamp the top of the valve so it doesn’t fall and remove the old seal like this:

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Swapping%20Seals/Stem%20Seal%2001.jpg

2. You will see from the pic below that there is not enough space around the valve to slide the seal past the rocker. I tried to stretch and manipulate one as well as trying to lower the rocker arm to increase the gap but ended up nicking a chunk out of the seal. Again, another method that required more hands than I had to press the rocker down and safely manipulate the seal without causing damage. With the clearance I achieved the gap was still too tight… you may fare better.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Swapping%20Seals/Stem%20Seal%2007.jpg

3. The option I went with was to move past TDC just enough to sit the valve on the piston but still have the tip of the stem showing enough to fit the new seal. The picture below shows how far I went to lower the piston but still see the valve and it was approximately two teeth on the pulley of travel.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Swapping%20Seals/Stem%20Seal%2002.jpg

4. With the valve safely lowered there is just enough clearance to slip the seal over the top.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Swapping%20Seals/Stem%20Seal%2003.jpg

5. You will notice in the picture above that the new seal has been turned inside out. Several people online recommended this method. Turn the seal inside out, slide the seal onto the valve upside down and then when it touches the valve guide roll the seal over itself from top to bottom. As the seal flips the right way it should seat in the groove around the guide… I tried it this way and didn’t get on with it. The rubber is pretty rigid and doesn’t like being manipulated too much. It eventually flipped but didn’t go over the guide, so it was back to square one. Again, you may get on with it better than me but I went a different way about it.

6. I took the new seal and warmed it up by running it between my fingers so it was slightly more flexible and then put some fresh oil inside and on the valve stem. I then used an allen key in the top of the seal with the tip wedged in the groove that slips over the valve guide and slid them both over the top of the valve. I didn’t get to take a picture as I did it but mocked this up after to show what I mean.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Swapping%20Seals/Stem%20Seal%2004.jpg

7. From here I ran the allen key around the edge of the seal and lifted it over the guide as it went. As the first part pops over hold it in place with your finger as it will try to pop off as you move around. Use your thumb and forefinger to give it a quick massage after to ensure that it is fully seated all around.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Swapping%20Seals/Stem%20Seal%2005.jpg

8. Slide the valve up enough to re-clamp it and then rebuild as above with your fresh new seals.

http://i4.photobucket.com/albums/y134/Macflurry/Monster%20M900/Valve%20Adjustment/Swapping%20Seals/Stem%20Seal%2006.jpg

Macflurry
02-09-2018, 11:57 PM
6. Additional Info.

Clearances should be checked every 6,000 miles (recommended).
Using MBP retainers instead of standard collets can extend servicing intervals but also require MBP shims to work with them. (Available from https://emsduc.com/)

Useful Links:

Most people swear by Chris Kellys Guides for DucatiTech/CA Cycleworks:

http://www.ducatitech.com/2v/maint/adjust/
https://www.youtube.com/watch?v=dIj3nSJGPZw&t=298s

DucatiSuite is a useful blog for info maintenance and modifications:

http://www.ducatisuite.com/valves.html

Mostly for older Ducatis but still has useful articles and links:

https://www.ducatimeccanica.com/desmo_valves.html

Macflurry
02-09-2018, 11:57 PM
7. Remarks

1. Clearance spec's table didn't copy over neatly. Will reformat it and re-add it in the morning. (Temporarily added as .jpeg)
2. Pic's are all over the place in size, feedback needed for if they should be adjusted?? ***
3. 4V clearances and info source required.

Macflurry
02-09-2018, 11:58 PM
***Reserved***

Macflurry
03-09-2018, 01:36 AM
Still work to be done, bits to be added, images to tidy up and facts to check.

Please let me know anything that needs adding or changing!! :thumbsup:

Hopefully it helps someone in the same position I was. Looking forward to hearing your feedback.

Enjoy!!

slob
03-09-2018, 06:10 AM
Haven't had time to read it all yet but:

in section 2, the first thing to stress is the engine must be stone cold (left overnight) before you start making measurements

Macflurry
03-09-2018, 07:33 AM
Haven't had time to read it all yet but:

in section 2, the first thing to stress is the engine must be stone cold (left overnight) before you start making measurements
*** Added ***

Awesome, thank you. It's stuff like this that I need to try and build it up and fix any errors. ;)

350TSS
03-09-2018, 07:44 AM
Brilliant - just about to tackle this job for the first time - thanks so much for taking the time and trouble to document your experience and post it here

Dukedesmo
03-09-2018, 10:15 AM
Using MBP retainers instead of standard collets can extend servicing intervals but also require MBP shims to work with them.

MBP retainers are great, I hardly need any adjustments on both my M900 and 916 but you don't need to use the modified shims in 2v engines, only the 4v require them and then only the opener shims.

As far as stopping valves from falling into the cylinder, I find it easier to remove the belts and turn the piston up (gently) to stop it falling.

Good info though. :thumbsup:

Mr Gazza
03-09-2018, 10:24 AM
Well done Macflurry. Blue Peter badge and bar for this thread. :thumbsup:

I must learn to do my own valves, as I dread the day that Carl Harrison retires. I always entrust this job with him, the only job I don't do myself.

From my observations and not experience... I think when all the measuring is done and it's time to remove the collets or "half rings". You can slip the belts off and keep the piston at TDC to catch the valve. The cam can then be rotated to the best place to get the rockers out of the way.
A magnetic probe (screwdriver or whatever) should be used to pick the collets out.
This is particularly useful if the rings have broken up, which mine seem to do every time!
Not sure if the allen key would stop the little bits that result?

I thought that MBP collets fit the standard shims, I believe that one of the selling points is that they fit them better than the half rings?
I have heard that the MBP collets can embed themselves into the valve stems making them impossible to remove without having the head off and cutting the valve.

Edit... Oops sorry I almost duplicated DD's post!

Macflurry
03-09-2018, 10:27 AM
MBP retainers are great, I hardly need any adjustments on both my M900 and 916 but you don't need to use the modified shims in 2v engines, only the 4v require them and then only the opener shims.

As far as stopping valves from falling into the cylinder, I find it easier to remove the belts and turn the piston up (gently) to stop it falling.

Good info though. :thumbsup:


Thank you. ;)

I'll add that in there as an option later today. The more info the better to cater for different approaches. Totally makes sense. When I started doing it I was trying to avoid taking as much of it apart as possible thinking it would be quicker and simpler but with the time I wasted trying to do that I may as well have slipped the belts off!!:banghead:

Dukedesmo
03-09-2018, 10:34 AM
You can get a much better 'feel' for valves if you turn the cam by hand, especially if looking for tighter closer clearances. IMO as tight as possible is better but obviously without any binding.

I find that once you are reasonably happy with the clearances, you can feel just how tight, tight really is by sticking a feeler in the gap (to take up the clearance) and then turning by hand to feel any drag...

Macflurry
03-09-2018, 10:43 AM
Definitely. I've since removed my cylinder heads and fully get what you mean about the feel for it now you've said it. My gaps have reduced so far that by hand you could feel one binding but when it was on the engine with belts it didn't translate through using the wheel to turn them as the momentum of the engine turning over carried it through the friction easier.

Hmmm, looks like some rewrites coming up on the horizon already. Thanks again.

Macflurry
03-09-2018, 12:22 PM
Well done Macflurry. Blue Peter badge and bar for this thread. :thumbsup:

I must learn to do my own valves, as I dread the day that Carl Harrison retires. I always entrust this job with him, the only job I don't do myself.

From my observations and not experience... I think when all the measuring is done and it's time to remove the collets or "half rings". You can slip the belts off and keep the piston at TDC to catch the valve. The cam can then be rotated to the best place to get the rockers out of the way.
A magnetic probe (screwdriver or whatever) should be used to pick the collets out.
This is particularly useful if the rings have broken up, which mine seem to do every time!
Not sure if the allen key would stop the little bits that result?

I thought that MBP collets fit the standard shims, I believe that one of the selling points is that they fit them better than the half rings?
I have heard that the MBP collets can embed themselves into the valve stems making them impossible to remove without having the head off and cutting the valve.

Edit... Oops sorry I almost duplicated DD's post!

Thanks bud!!

The allen key definitely wouldn't stop shattered parts. I was wary that it may not stop whole collets but I could have used a bigger key. I read a couple of peoples pages saying to use ear plugs, which makes sense if you get the tapered ones, then they would fit nicely.

I've personally not used the MBP parts but one of the blogs read that if you used them you had to swap out the other parts. I'm happy to take peoples direct experience over what I've read on the net as the info I saw may be outdated. I'll also head to the manufacturer site later today and see if there's anything else to be aware of.

Belts off definitely seems to be the way forward. When I first started taking things apart I was wary of touching them as it was something else to go wrong as it went back together. But since taking them off after it isn't as bad as I thought... will confirm that once it's back together though!!:D

Nasher
03-09-2018, 12:51 PM
Great thread well done, I just wish you'd put it together before I did my first set of valves last year.:D

It's a slightly tricky operation, and you do need to be able to use a set of feeler gauges well, but it's a satisfying process if you like that sort of thing.

It's a little annoying however when you work out the exact shims you need and they are not available, so you have to resort to the nearest slightly out of tolerance one, or touch the top of the valve etc on a grinding wheel.

I must admit I had the benefit of the engine being on a stand and in bits, so I did the valves with the heads on the bench.

It did occur to me that on a Monster where the heads come off with the frame and the engine assembled it's possibly worth taking the heads off and doing them on the bench where access isn't a problem.
The engine I was doing at the time is from my SS project, and the vertical head doesn't come off with the frame fitted to the engine.

Again - Well Done.

Nasher

Macflurry
03-09-2018, 04:05 PM
Great thread well done, I just wish you'd put it together before I did my first set of valves last year.:D

It's a slightly tricky operation, and you do need to be able to use a set of feeler gauges well, but it's a satisfying process if you like that sort of thing.

It's a little annoying however when you work out the exact shims you need and they are not available, so you have to resort to the nearest slightly out of tolerance one, or touch the top of the valve etc on a grinding wheel.

I must admit I had the benefit of the engine being on a stand and in bits, so I did the valves with the heads on the bench.

It did occur to me that on a Monster where the heads come off with the frame and the engine assembled it's possibly worth taking the heads off and doing them on the bench where access isn't a problem.
The engine I was doing at the time is from my SS project, and the vertical head doesn't come off with the frame fitted to the engine.

Again - Well Done.

Nasher

Thanks Nasher.

Now I've gone in to swap the o-rings out for my cylinder heads they definitely came out easier than I expected. The hard part is clearing out the parts around them to remove. Had a few incidents requiring a dremel with seized stud nuts but nothing crazy.

If the engines had a lack of TLC all the nuts bolts and flanges soon add up for replacements.

But on the plus side it is so much easier to work on and you can clean it up and get your valves lapped in again before doing your adjustments and getting your new shims.

My issues are on the vertical head. I thought I may as well take the horizontal one off too while I'm at it to get them both cleaned up nicely inside. Lucky I did as I found one of my valves was very slightly bent which I wouldn't have found if I hadn't!!:worried:

Still sealed OK before swapping it but it's a warm fuzzy feeling knowing you've put something else right!!

Dukedesmo
03-09-2018, 06:02 PM
It did occur to me that on a Monster where the heads come off with the frame and the engine assembled it's possibly worth taking the heads off and doing them on the bench where access isn't a problem.


Maybe, but I wouldn't be happy to remove the heads without also removing the barrels because you'd likely get an oil leak from the base afterwards if not. And that means scraping off the goo from the base gasket/shims - then whilst in there I'd want to clean up the pistons and rings - I then would have to clean up the inside of the heads, valves and ports, re-seat the valves, replace the 'O' rings and threebond the bases gaskets.

All of which becomes a much bigger job than simply changing a few shims.

If you think access to the valves with engine in the frame is limited, you should try changing shims on a 916 rear cylinder exhaust valves...

jerry
05-09-2018, 03:50 PM
superb thread mate brilliant ,, I have done many 2 & 4v shim services and sometime one has to be a gynacologist especially on 4v models ,, if starting from scratch with new valves or rockers its often easier to do them with heads off on the bench .

Macflurry
15-09-2018, 07:14 PM
Hi guys just as an update:

After reading around the net a lot of people were recommending EMSDUC in the US for shims, even to UK buyers, as a good alternative to Ducati. I get they do the shim kits that would be a God send for regular maintenance but I thought I'd try my luck just ordering what I needed for a start.

So I've ordered 6 shims. 2 openers at $8.50 and 4 closers at $9.50 totalling $55 or £42.08. So far so good... but shipping on top was $33.95 which brought it to a total of $88.95 for the order or £68.06.

I placed the order on the 1st Sep thinking I should have them within a week as peoples reviews said stuff showed up fast from the US. I got the customs letter through the post today to pay the import duty on them and they can deliver Tuesday at the earliest so 18 days to arrive plus and extra £24.88 for import duty.

So the grand total £92.94 and 18 days door to door for 6 shims.

For comparison at https://www.bike-parts-ducati.com the Openers are £11.62 and the closers are £24.80 each. The postage is only £6.99 but the order total would have come to £129.43 door to door.

Another site, StarTwinMotors at www.oemducati.com, are £9.40 for openers and £20.06 for closers so my order total would have been £99.02 but didn't get to see the shipping price as I had to start accepting terms and conditions to go further.

So to round it up the parts only total for each site:

EMSDUC £42.08 + £24.88 duty = £66.96
Bike-Parts-Ducati = £122.44
Star Twin Motors = £99.02

And postage costs:

EMSDUC £25.98
Ducati = £6.99
Star Twin Motors = £ Not Known

EMS come in as being the cheapest even without knowing the cost of Star Twin Motors postage. Although the postage is a bit pricey as a jet kit I ordered from the States was only $18 to ship back from a different vendor. But if you need the parts faster you would have to put your hand in your pocket for one of the others.

If anyone can recommend any more places in the UK for getting them at a decent price then drop the name in a reply and I'll add links to the opening posts.

Mr Gazza
15-09-2018, 08:10 PM
I have the utmost respect for folks who do their own valves and I still feel bad for not doing my own, but..
When Carl Harrison charges about £120-150 to do the whole job including whatever shims are needed and new half rings if necessary.
I only miss the bike for a couple of days and don't have to wrestle with the airbox and wiring harness. The belts come off for the operation and so are checked when they go back on. If I supply new belts, then those go back on instead of the old ones, so free fitment, so to speak.
It's still making a lot of sense to me, to have Carl do my valves, even though I know the time will come.

Macflurry
15-09-2018, 08:38 PM
For that price/time frame it makes a lot of sense to hand it over.

I guess if you've already paid out for a full shim kit then job for job the cost becomes minimal just to swap some out and then only buy odd ones as needed. The 8mm shim kit is $269, which is £205. So 2 maintenance periods in and you're saving. If you're definitely keeping the bike long term, have more than one bike that can use the same kit or you're racing and constantly checking and maintaining tolerances then it becomes a cost saver. For casual riders that don't rack up ridiculous miles then it may not be worth the hassle.