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Changing and checking shim clearances

20K views 48 replies 13 participants last post by  Figifister 
#1 · (Edited)
1st tip: Use the same unit of measurement throughout the whole process. MV lists Metric specs. This will throw you off if you don't pay attention to your feeler guage. Most guages list BOTH SAE and Metric.

2nd tip: Be clean and organized. Someone once said the lazy mechanic works the hardest.

3rd tip: Line up your timing marks! 3rd cylinder needs to be on TDC and both cam marks need to be facing outward. Doing this also aligns all the cam lobes in a such a way to "unload" the valve springs. Now you can unbolt the cradle in a outside to outside and opposite sequence. Use a standard T30 torx drive socket.

4th tip: Use a strong magnet to remove the buckets! They designed the shim to be just small enough to fall into the oil galley return hole...ask me how I know. By the grace of God my magnet was EXACTLY the perfect size to fit down the hole and retrieve the lost shim! Can you believe that!? I thought that I would have to take the oil pan off at least and at worst remove the head depending on where it decided to run off to. Cant tell you how great that feeling is when I heard the "click" of the shim sticking to the magnet! Learn from my mistake.

5th tip: When figuring shim thicknesses shoot for the middle of the range. That way if your new shim is +/- the advertised thickness your still within the range. Also say your old shim has a advertised thickness of 1.95mm but it mic's out to be 1.93mm. Always go with the micrometer measured thickness. But keep in mind MV only has shims in .05mm increments that's why it's important to shoot for the middle of the range because while you may need a 2.07mm shim they only offer 2.05mm and 2.10mm. So you have to make a decision to error on the side of caution and pick the smaller shim...But still stay within the acceptable range. Shoot for the middle! (.20mm for Intake and .25mm for exhaust)

6th tip: Use a valve lash calculator. It's pretty simple and takes the human error out of the equation. You have enough to the think about as it is!

7th tip: Re-installation use a light amount of moly assembly grease on all metal contact surfaces. Place the shims on top of the valve spring retainer just above the valve THEN slide the bucket over the top of the valve.

8th tip: Always double check your work. Re-verify clearances when you install the camshafts and tighten the cradle and put the tensioner back in. Rotate the engine two revolutions, then check the clearances. Do this untill you have all of the measurements where you need them. *Note you may need to do this process 3 or 4 times to verify that your numbers do not change!

9th tip: Do this service when you also need an oil change. It is a good idea to change the oil in case any dirt got into the head and oil when you were working.

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*Update


10th tip: Change out your Hydraulic timing chain tensioner for a manual tensioner! This will accomplish two things. First it will provide constant tension on the chain no matter the RPM (oil pressure). Secondly it will insure your timing does not change or accidentally slip! As you can see in the two videos I have posted the Exhaust cam wants to slip and you can see the chain lifting up. This is exacerbated by the running of the engine and the torque loads (pulses) put on the chain. MOST of the failures you have heard of are from the exhaust valves! MV agrees with this as they are implementing 2018 and newer engines with a manual tensioner. The same manual tensioner, believe it or not, can be found on a Polaris RZR 900/1000. It is dimensionally identical. You can purchase an OEM MV, Polaris, or a quality aftermarket version.

(Some of this information has already been discussed in other parts of the forum and using a Polaris tensioner was not my original idea. I wanted to create a clear concise place for people to know all the helpful tips and I will update this as time goes on.)


Have fun! Ride safe.




Watch "MV Agusta F3 800 / 675 Part 1 and 2 comparing hydrualic tensioner to Manual" on YouTube

 
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#7 ·
Hi,
Thanks for this,
I've been trying to check the valve clearance on my F3 675 2014.
I took of the head cover and the alternator cover, the marks on the camshaft and the phonic wheel were almost alined.(I added photos)
1. I can turn the crankshaft only about 15 degrees the it stuck, on both directions.
2. It seems that the 2nd piston is in TDC and not the 3rd according to the manual its supposed to be the 3rd.

How should I continue?
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#11 ·
Only rotate crank in direction of normal running.....going the other way for very far can engage the starter sprag.
 
#14 ·
Thank everyone I managed to turn the crankshaft and measure the valve clearance.
I have 3 intake valve that are out of spec.
The play spec. according to the manual are 0.15-0.24.
The 0.2 filler is not fitting, the 0.15 is clear.
should I replace the shims? its similar in all the 3 valves that are out of spec.
 
#15 ·
It is a go/no-go measurement.....if the smaller gauge goes in and the larger does not then the valves are in spec.
 
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#19 ·
Valves tend to tighten up over time.....they only get loose when carbon deposits prevent the valve face from seating fully.
Shims only come in .05mm increments.....If your measurements are within the range....the smallest gauge goes in easily and largest will not...you are better off leaving them alone.

If you have to force the smallest gauge, or it is very tight, then you should replace the shim for the next smaller size.
If the largest gauge goes in without forcing, or is loose feeling, than replace with next larger shim.

If you are building a true race engine and you want precise clearances for performance reasons, you will need to be able to shave shims to create the size you need.
 
#21 ·
I'm in the process of checking my valve clearances on my 2015 F3 800. I've reached the stage of having the bike at tdc for cylinder number 3 with the notch on the phonic wheel lined up. After I check the clearances for intake and exhaust cylinder 3 do I simply rotate the crank untill another cylinder cams appear in tdc position. Thanks
 
#28 ·
Clearances checked now preparing to remove the cams
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have checked valve clearances and now preparing to remove the cams. When I check the line up for TDC the phonic wheel does not line up? The I marks on timing chain and cams seem ok and number 3 cylinder cam lobes are both pointing inwards. Is this unusual or safe to proceed. I included pics of the current alignment of the cams.
 
#32 · (Edited)
Its definitly NOT correct. Re-assemble according to the manual and the info/photos you have seen on this site.

This can happen if you don't check your marks AFTER installing the tensioner. It will move. You then need to remove the tensioner and rotate the crank forward or reverse a tooth depending on whitch ever direction your off.

Sent from my SM-G930V using Tapatalk
 
#33 ·
Its definitly NOT correct. Re-assemble according to the manual and the info/photos you have seen on this site.

This can happen if you don't check your marks AFTER installing the tensioner. It will move. You then need to remove the tensioner and rotate the crank forward or reverse a tooth depending on whitch ever direction your off.

Sent from my SM-G930V using Tapatalk
Thanks for this advice. Will start removing cams in next few days. No hurry now I recently had a fall and # fibula on my left leg, so non weight bearing for about 4 weeks.
 
#34 ·
Still experiencing issues with the phonic wheel after shim adjustment. I line the phonic wheel to TDC and then align the exhaust and then inlet cam. Put cam cradle on not tightened then tighten the CTC then torque down the cam cradle. When I rotate the crank the phonic wheel always moves out of alignment. Unsure how to fix this. Thanks
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#37 ·
Appears I have a faulty hydraulic cam chain tensioner, I have ordered a manual tensioner to replace this. Initially the phonic wheel was slipping, then later the cct was stuck at full extension and timing chain was so tight I was unable to rotate cams.
 
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