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Discussion Starter #1
G'day All,
How critical is it to change the cam chain at 30,000 km? Seems a rather low figure compared to other engines. Is it a complete engine tear down to change it? I cant see where in the engine manual it gives the procedure.
 

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Depends on how hard you flog your bike and how clean you keep your oil. It is a roller chain, just like the drive chain. You can measure the stretch and determine wear if concerned.

As for replacement, I do believe it can be done engine in frame, just remove cams. You will need a chain breaker/riveter made for a cam chain.

The replacement chain is available open with an "master" link. I'm sure someone here has done this (or maybe had it done?).

I do not plan on replacing my cam chain so soon...actually, I already exceeded 30,000 km anyway.
 

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?

Don't think you can do it that way Ed.....
Look at page B85 of the engine manual
The Dagos built differential gearing into the idler gear.....so the timing marks on
The idler gear only align after many revolutions of the crank.....
And they don't say how many

AND IT'S NOT AT TDC :surprise::surprise::surprise::surprise::surprise::surprise:
So you can't take the cams out, they'd need to be locked in place before the chain is cut
I don't know if there's room between the idler sprocket and the crank to fish a new chain through there


Aprilia RSVRs do the same stupid thing and it's 34 revolutions of the crank
 

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I think you can..... Yes, I know there is the idler gear driving the cam chain.

Set the crank at TDC #1. Remove the cam chain tensioner and cams, break the chain, fish the new chain through by pulling it with the old chain, rivet the chain, install and time the cams, install the tensioner.

Never turn the crank until time to check the timing to make sure you got it right. The idler gear is irrelevant.

I'll bet you $100 and a case of beer I can do it (having done similar on many old bikes with roller cam chains).

You supply the bike and parts. I'll supply the time and tools (yes, I have the proper cam chain breaker/riveter tool). If it doesn't work I will pay for the additional parts to split the cases and finish the job.


But to answer his original question.... I don't think he needs to replace the timing chain at 30,000 km ......do you? :wink2:
 

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No......not with 56,000km on mine

But looking at the picture on page B82 doesn't look like there is much clearance between the
sprocket and the crank

:wink2:
 

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Up date, just tried it on a motor with the cams out......

Used bent welding rod to try and push the chain down below the sprocket, didn't work

Don't want your beer or money

:wink2:
 

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Discussion Starter #7
Thanks blokes. I'm familiar with differential gearing, also known as a hunting tooth. The timing part doesn't bother me too much, I work on my Ferrari and Vincents. Given that I ride the MV 'sedately', and change the oil regularly, I think that I can probably let it go a little longer. The breaking and riveting the chain would make it a lot simpler. Thanks again.
 

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Up date, just tried it on a motor with the cams out......

Used bent welding rod to try and push the chain down below the sprocket, didn't work

Don't want your beer or money

:wink2:
Surprising....wonder why they offer the open chain then?

Well, not planning on trying it on my bikes either....not anytime soon anyway.

Thanks Noel.:grin2:
 

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All three of my Brutales have had the cam change replaced using the split chain provided by MV. You should play safe and do the tensioner at the same time, I know from experience the chain will snap if the tensioner gives up.... The guides are also supposed to be replaced with the chain.

I don't know exactly how my mechanic did it but the 1090 was done at about 72000km and the 910 at 60something. Think he said the 1090 was a bit tired and should probably have been done sooner, but that was 30000km ago now!
 

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Surprising....wonder why they offer the open chain then?

Well, not planning on trying it on my bikes either....not anytime soon anyway.

Thanks Noel.:grin2:
Ed;
For people that don't have the riveting tool, or can't rivet

:wink2:
 

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OK....Let's think this thing out.

The idler gear simply reverses direction of the crank rotation relevant to the cams.

You can remove the cams, break the chain, tie the new chain to the old one, rotate the crank to pull the new chain through, rivet the new chain together, rotate the crank to TDC #1, install and time the cams. Job done.

The idler gear is irrelevant. Once the cams are timed on #1 TDC as normal everything is back to....wait for it....NORMAL....except you have a new chain.

Sometimes my brain gets so tied up that the obvious eludes me.

Going to sleep now. I'm old and need my rest.
 

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My 910R is at 45,000 miles (72,000 km) and I've been thinking about the cam chain... I am thinking it may be beyond my capabilities to replace. In the manual they only talk about replacing it in the context of having most of the engine already apart. There doesn't seem to be a procedure to just replace the chain.
 

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Searching around the forum, I can across this thread:
http://www.mvagusta.net/forum/20-maintenance-tech-issues-all-4-cyl-models/22052-cam-chain.html

In post #14 (http://www.mvagusta.net/forum/20-maintenance-tech-issues-all-4-cyl-models/22052-cam-chain-2.html#post284935)

"Straightforward job - there's just enough clearance arond the bottom end that you can pull the new chain through with the old one by shaking & jiggling it, if you see what I mean - I don't remember having to rotate the engine at all which saves the risk of bashing valves."

Interesting that he seemed to be able to do it without rotating the idler gear.
 

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OK....Let's think this thing out.

The idler gear simply reverses direction of the crank rotation relevant to the cams.

You can remove the cams, break the chain, tie the new chain to the old one, rotate the crank to pull the new chain through, rivet the new chain together, rotate the crank to TDC #1, install and time the cams. Job done.

The idler gear is irrelevant. Once the cams are timed on #1 TDC as normal everything is back to....wait for it....NORMAL....except you have a new chain.

Sometimes my brain gets so tied up that the obvious eludes me.

Going to sleep now. I'm old and need my rest.
You must have been writing this at the same time I was writing my reply. What you are saying makes sense and seems very doable. This may be my "winter" project.

I think it is funny that in the manual, replacing the cam chain is on the maintenance schedule, yet when you look at the "Timing chain, mobile timing chain guide and timing chain tensioner" section, this is what it says: "To disassemble these parts and not being part of normal maintenance, it is necessary to proceed as described in the overhaul section of the F4 workshop engine manual..."

So it is on the maintenance schedule, but somehow not a part of "normal maintenance" :confused:

I guess replacing it every 45,000 miles or so isn't a huge deal - especially if I don't have to overhaul the engine in order to do so. I have a chain tool that is supposed to have the parts for a cam chain pin, so I should be okay for that part of it.
 

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Discussion Starter #16
Well thanks blokes. I don't ride my MV hard, rarely seeing 7-8,000rpm so it seems that I can let it go a bit longer before I change the chain. Changing the chain doesn't look like a big problem. I familiar with and have done chain breaks and chain riveting and cam timings so not a big problem there.
 

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Some advice. As I have recently done the valve clearances on my F4. Before you begin removing cams etc take note (photo) of cam gear marks when crank is in the correct position.
When reassembling lock the crank in position, partially insert the tensioner(without the spring and extended maybe 2 teeth less than when you removed it) with bolts just screwed in and bring your cams and tensioner down, and in, systematically. Your marks should be the same as your photo when all tightened up.
After many hours and attempts at
aligning the marks perfectly, I discovered that mine did not line up and the bike runs perfectly. As Noel has previously stated they have designed it so it all lines up perfectly after many revolutions.
Very bloody frustrating if you are unaware of this.
Don't be fooled by the manual as to how easy it seems.
 

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Don't be deterred by Noel's comment.
My 750 gets thrashed but has only ever run in 300V 10W50 changed regularly.
I removed the chain at 35000mi. In comparison to the new chain it hadn't elongated, side defection was minimal. Rollers were the same diameter. Cam sprockets mildly worn.
Conclusion - if cared for - don't bother. A CBR will do twice that on its chain.
Anyway I was committed, so wired it on the old chain and jiggled it through.
Hot tip** the cams don't have much fight in them at the timing marks location, so don't anticipate an elaborate clamping system. Use what you have but it doesn't need much.
Hot tip #2** replace the cam sprocket bolts with grade 8.8 (or higher) socket head cap screws if your model is an early one and doesn't already have them.
 

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