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My 2010 B4 Valve Adjustment Experience

2K views 10 replies 6 participants last post by  theknurl 
#1 · (Edited)
First of all, I would like to thank all of those who have posted previously with their experiences; which allowed me to go into this with a good idea of what was to come.

Knowing that the cam stand bolts are a known issue, I stripped the top part of the bike, including coolant overflow tank, to give myself room.

The first 15/16 cam stand bolts came out nice and easy. :shitfan:The final one rounded out instantly:crying:. I can honestly say that it was likely due to me skipping a step and not cleaning out the oil in the bolt. :bash:

Ended up getting a carbide bit and drilling the head out without damaging anything. Got the required shims swapped out; strangely once everything was buttoned up, my calculated values didn't quite pan out for some of them (expected 0.28mm gap on a few of the exhaust, got ~.26) any clues on this??


I decided the new gap was acceptable and proceeded to put her back together. Tried to Line up the intake and exhaust cam position lines, with 24 chain links in between and no go. The exhaust cam mark was dipping one tooth below the required plane. :wtf:

After ~5 times taking the cams off an redoing it perfectly, only to have the exhaust cam jump a link as I tightened the stands down, I figured it out! :idea:

I got it all to line up by first placing the cams in with mark lined up perfectly and 24 links in between. Then I placed cam stands 2 and 3, tightening them progressively back and forth just enough to hold the cams in place. I then installed stands 1 and 4 and did the same. At this point, I installed the CCT and hand tightened it enough to keep tension on the chain to prevent the cams from jumping as I progressively tightened the stands (First 2 and 3, ten 1 and 4) down the remaining amount. I also kept redoing the hand tightening on the CCT to keep tension on the chain.

I could hear the CCT extending as I tightened the cam stands down. Finally, with all the cam stands down to 12Nm, I tightened the CCT to 12Nm, then turned the engine thru a few cycles. Again, I could hear the CCT extending as I did this.

End result is that the cams retained the 24 chain pins between the marks, TDC mark was dead on, and the cam marks are dead parallel with the block.



:confused:Question. I peeked down the timing chain at the CCT and noticed that the ratchet spring was damn near on it's way out. I stuck a tool down and pushed it level, but should I be concerned that it could pop out under normal operation? Currently has 6 notches extended, how many notches does it have fully extended?


I almost threw in the towel at several points and towed it to a shop, but thanks to this site I was able to pull thru and get it done. Haven't fired her up yet as I just finished this before work today, will finishe putting her back together in the next week and see if she doesn't blow up. :brutale:
 

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#3 ·
You're good.... well done.
Did you measure the shims you removed with a micrometer, or just use the numbers etched on them? Could explain the variance. Always a good practice to measure shims with a mic (R1andrew....I know...we didn't do this, but it turned out fine!!!)
 
#4 ·
Thank you! Yours and @ revhead1957 comments on the other posts helped alot. Yes, I did measure the all the shims with a micrometer to double check, it went into the calculation of the new shim size. See attached for the spreadsheet I used.

I really don't understand the variance. I've read on other forums that once everything is snugged down, the calculated values may not always pan out, but no idea why haha.
 

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#5 ·
Nice spread sheet.....of course, we're dealing with feeler gauges here. And sometimes that "feel" may not be perfect. I use the "Go - No Go" method where I use the lowest clearance spec and the highest clearance spec feelers. As long as the smallest slips in easily and the largest doesn't go without force I am happy.


Of course, being a bit OCD, I will then try to determine the actual just to drive myself crazy. :ahhh:
 
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#7 · (Edited)
Ugh - the hex head bolts round out? Fun. Are they made of cheese-metal? Anyone popping them off with an air gun to break them loose fast vs stripping slow? Replace them with high grade or just factory?

That's a lot of shims to have to replace!

I'm happy to see they take 7.48mm diam shims, as I have two shim kits for "Kawi's" in 7.48mm that I used on my Z750S and my friends ZX6R back in the day.
 
#8 ·
The one that rounded out was my fault. I didn't clean the oil out of the bolt head first. I think that if it's dry and you use an impact, it comes out smoothly. Lessons learned haha
 
#9 ·
Wish I had known you were doing this back then, would loved to have helped. I've done plenty of valves over the years, always nice to learn by watching on another's bike for the idiosyncracies.

Maybe when mine are due we can have an MV valve check maintenance "party". I've done them for the Ducati clubs in the past.
 
#10 ·
I would've loved to have some help. I had to bring the wife in a few times for a helping hand. :laugh:.
Let me know when you're ready to do yours and I'll come by, with beer! :friday:
 
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