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Discussion Starter #21
Hello!!
They told me that ALL THE VALVES were out of specs.... too tight. They had to shim them all. The intake ones not too bad, but the exhaust ones very tight. That what they told me when I picked the bike up and they charged me for on the invoice. Thank you
In addition, they told me they had to take the time belt off, therefore surely the camshaft as well. Thank you
 

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Hello,are you very mechanically minded.Even changing the shims won’t cause valve collets to dislodge after 500 miles,it would happen pretty quickly.Maybe the cam timing was out and the pistons were touching the valves.Just thinking.
 

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Hello,are you very mechanically minded.Even changing the shims won’t cause valve collets to dislodge after 500 miles,it would happen pretty quickly.Maybe the cam timing was out and the pistons were touching the valves.Just thinking.
You are right. And if timing were off you would definitely hear it, no? Now if I left a tool or a bolt lying around in there😱
 

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Discussion Starter #24
Hello,are you very mechanically minded.Even changing the shims won’t cause valve collets to dislodge after 500 miles,it would happen pretty quickly.Maybe the cam timing was out and the pistons were touching the valves.Just thinking.
Hi!
I am mechanically minded as actually I do some work myself to my bike. To be honest though I am not familiar with valves... but to me it sounds too much of a coincidence that engine was flawless for 27500 miles, they put their hands on and after 500 miles a disaster happens. (and mechanical failure might be for 1 valve...BUT 2??).
That is the main reason I reached out on this forum at this highly knowledgeable awesome community/family to gather opinions ( and I surely know you are one of them...!).
If I may reply to your suggestion of the piston touching valves with a question....
Wouldn't be possible to hear such a contact with a noise or light bang? Thank you
 

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Hi!
I am mechanically minded as actually I do some work myself to my bike. To be honest though I am not familiar with valves... but to me it sounds too much of a coincidence that engine was flawless for 27500 miles, they put their hands on and after 500 miles a disaster happens. (and mechanical failure might be for 1 valve...BUT 2??).
That is the main reason I reached out on this forum at this highly knowledgeable awesome community/family to gather opinions ( and I surely know you are one of them...!).
If I may reply to your suggestion of the piston touching valves with a question....
Wouldn't be possible to hear such a contact with a noise or light bang? Thank you
As you I am not super mechanically minded. However, I did take on the job of doing the valve clearance/shimming job myself. You can see my posts on the subject here. I still have my fingers crossed that I did a good job. Have not put 500 miles on the bike since I did it. One noticeable difference is that there is no longer the inconsistent RPMs at Idle. She also seems to have a throatier sound. The engine is noisy to begin with so I could not say. But I THINK that if my valves were touching anything there would be a loud ticking sound. I could see on of the cam cover bolts coming loose if not properly torqued and falling into the engine. So many variables it is hard to pinpoint. The veteran members will chime in here.
 

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Is the company taking it apart now for the assessment the same company that did the valve check?
 

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In addition, they told me they had to take the time belt off, therefore surely the camshaft as well. Thank you
Well...it is a timing CHAIN....no belts on the MV engine. And yes, they would have to take the cams out to make adjustments, therefore lifting the timing chain off of the cams....but they didn't remove it.
But that is all semantics.....sounds like they may have made a mistake somewhere. Since only one cylinder involved, and the bike ran OK prior to failure, I would not expect missed cam timing.
A shim not seated fully, shifting out of position and holding valve open too far resulting in piston contact, more likely.
Is that a valve collet you have a photo of? If a shim shifted out of place the collets could come loose causing this failure.
478371

Sad to see this failure. Good luck in your quest for compensation. MV will not likely take any responsibility in this failure....and I don't think they should. At the mileage you have, and the services done immediately prior to failure, I don't believe this is a defect in manufacturing or materials.
 

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Discussion Starter #29
Well...it is a timing CHAIN....no belts on the MV engine. And yes, they would have to take the cams out to make adjustments, therefore lifting the timing chain off of the cams....but they didn't remove it.
But that is all semantics.....sounds like they may have made a mistake somewhere. Since only one cylinder involved, and the bike ran OK prior to failure, I would not expect missed cam timing.
A shim not seated fully, shifting out of position and holding valve open too far resulting in piston contact, more likely.
Is that a valve collet you have a photo of? If a shim shifted out of place the collets could come loose causing this failure.
View attachment 478371
Sad to see this failure. Good luck in your quest for compensation. MV will not likely take any responsibility in this failure....and I don't think they should. At the mileage you have, and the services done immediately prior to failure, I don't believe this is a defect in manufacturing or materials.
Hi! Thank you for your reply....Sorry I meant chain....( Catena di distribuzione in Italian, not very familiar at times with mechanical English terminology) . I agree with you that was NOT a defect in manufacturing or materials. Mv USA told me that they passed the ball to MV in Italy. I reached out to Mv USA this morning offering my input and solutions that I gather from this community so far and other friends with knowledges. The gentleman, named Michael, doesn't think the mechanic is to blame.... I disagree and wrote an email to Mv in Italy....Let's see what happens
 

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The shims sit in a recess in the buckets which sit on top of the valve stems.
Cannot see how a shim could cause this failure.
If the 2 exhaust shims on the failed cylinder were too thick the motor would have had loss of compression
and would have run very rough and popping at idle.
You would have noticed this straight away.
The only thing I can think of is valve timing was not correct causing valves to touch the piston and over time
the valves finally snapped off.
Still doesn't explain why the rod let go.Bit confusing.
Really hard to say without inspection.
 

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Mitchy, according to the OP, the rod didn't break. The piston broke and a piece fell between the rod big end and the cases... knocking out the hole. I've seen similar happen before, so I can believe that.
If the shim is not fully seated and is riding crooked on top of the retainer it can come out....but you have to not be paying close attention at installation...OR a shim too thin was installed in error allowing the lifter cup to ride directly on the retainer which would allow the collets to float out.
The fact only one piston was contacted by valves would seem to indicate the cam timing wasn't off...otherwise all 3 cylinders would have had valve contact.
Just trying to think of possible ways for valve collets to come loose and result in this failure.... Pretty sure at 28k miles it didn't originate in manufacture.
But who knows...I would love to be doing the forensic inspection myself.
 

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Discussion Starter #32
Mitchy, according to the OP, the rod didn't break. The piston broke and a piece fell between the rod big end and the cases... knocking out the hole. I've seen similar happen before, so I can believe that.
If the shim is not fully seated and is riding crooked on top of the retainer it can come out....but you have to not be paying close attention at installation...OR a shim too thin was installed in error allowing the lefter cup to ride directly on the retainer which would allow the collets to float out.
The fact only one piston was contacted by valves would seem to indicate the cam timing wasn't off...otherwise all 3 cylinders would have had valve contact.
Just trying to think of possible ways for valve collets to come loose and result in this failure.... Pretty sure at 28k miles it didn't originate in manufacture.
But who knows...I would love to be doing the forensic inspection myself.
Morning!!
Thank you for your reply!!
I haven't been up to the mechanic and I think they took only the tank off and the body throttle off as you can see from pics.... At that point the mechanic stopped the work, took the photos, got in contact with Mv USA and they reached what I think It is the wrong conclusion of a manufacture/quality issues with valves, as the problem has happened before (mostly on 675cc and they told me it always happens to cylinder #2).
Mechanic has been told to do not continue the AUTOPSY....
Braking of piston is so far only a deduction...
Thank you,
BY THE WAY...I would love you to do the AUTOPSY!!!! :)
 

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Most of the bikes that have had valve failures have had them on the intake side and not the exhaust. Please keep us in the loop as to the cause of failure.
 
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