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Author Topic: hyvo cam chain failure on the 718??  (Read 2868 times)

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Offline paulages

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hyvo cam chain failure on the 718??
« on: June 13, 2009, 12:28:02 PM »
howdy folks. i just returned from a two month tour of europe, just in time for perfect riding season in portland. i was doing some maintenance last night to get the bike ready to ride, and found a piece of the cam chain in the oil pan...

the piece is one of the plates on the side of the chain that holds the links together (like the master link plate on a duplex chain). there is no sign of wear or anything on the piece, and it was just this one piece. obviously i have to pull the cam cover off and find where it happened, and will surely have to pull the engine and replace the chain, but i'm curious if anyone's ever seen this happen? brand new OEM chain, with only a few thousand miles on it. high RPM miles, but still...

 :-[
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paul
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Offline kghost

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Re: hyvo cam chain failure on the 718??
« Reply #1 on: June 13, 2009, 12:30:34 PM »
Europe sure is fun.......Need to get back there one of these days...


I've seen chains come apart...when there was a manufacturing defect.

I've seen them come apart while being used in an application they were not rated for...
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Offline mlinder

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Re: hyvo cam chain failure on the 718??
« Reply #2 on: June 13, 2009, 12:32:34 PM »
Damn, Paul, that sucks....

Welcome back, heh.
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #3 on: June 13, 2009, 12:44:10 PM »
Quote from: kghost on June 13, 2009, 12:30:34 PM
Europe sure is fun.......Need to get back there one of these days...


I've seen chains come apart...when there was a manufacturing defect.

I've seen them come apart while being used in an application they were not rated for...

I'm mostly surprised because it's a hyvo chain, riveted together. It looks like one of the rivets must have failed.

Thanks mark.. guess I won't be riding for a little bit.
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paul
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Offline kghost

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Re: hyvo cam chain failure on the 718??
« Reply #4 on: June 13, 2009, 12:47:20 PM »
It happens....

Sometimes the rivets don't get smashed quite enough....

Also sorry to hear of your travails...

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Offline nokrome

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Re: hyvo cam chain failure on the 718??
« Reply #5 on: June 13, 2009, 01:02:37 PM »
hi paul, welcome back
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #6 on: June 13, 2009, 01:35:50 PM »
Quote from: nokrome on June 13, 2009, 01:02:37 PM
hi paul, welcome back

Thanks phil! We'll get to work on your head asap.
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Offline bwaller

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Re: hyvo cam chain failure on the 718??
« Reply #7 on: June 13, 2009, 01:59:43 PM »
That bites Paul. Can't even say it's a teething problem when it's a new OEM chain.
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #8 on: June 13, 2009, 02:14:26 PM »
Quote from: bwaller on June 13, 2009, 01:59:43 PM
That bites Paul. Can't even say it's a teething problem when it's a new OEM chain.

There was no metal in the filter or pan either. I think it just popped off the rivet and I caught it before the while link came apart.
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Offline scunny

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Re: hyvo cam chain failure on the 718??
« Reply #9 on: June 13, 2009, 03:37:18 PM »
that sucks, those chains look indestructable.
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #10 on: June 13, 2009, 04:21:53 PM »
Quote from: scunny on June 13, 2009, 03:37:18 PM
that sucks, those chains look indestructable.

I guess tensile stength (would that be the right term here?) doesn't mean anything if the links are riveted poorly.
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paul
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Offline bwaller

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Re: hyvo cam chain failure on the 718??
« Reply #11 on: June 13, 2009, 05:27:53 PM »
It's a good thing you pulled the pan.
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #12 on: June 13, 2009, 07:20:58 PM »
Quote from: bwaller on June 13, 2009, 05:27:53 PM
It's a good thing you pulled the pan.

i'll be pulling the pan every oil change on this engine for a while. the pain in doing this is that i have to pull the exhaust to do so. i'm headed down there now to pull the cam cover and inspect the chain, but i'm expecting to have to start tearing it back down this week. at least i can leave the cylinders alone, but i'll have to split the cases, split the rods, and re-time the cam upon reassembly. not how i pictured my first week with the bike after returning... could have been worse though.
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paul
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Offline WFO

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Re: hyvo cam chain failure on the 718??
« Reply #13 on: June 13, 2009, 07:25:50 PM »
Quote from: bwaller on June 13, 2009, 05:27:53 PM
It's a good thing you pulled the pan.


Heck! it's good thing it made it to the pan  ;D
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Offline MRieck

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Re: hyvo cam chain failure on the 718??
« Reply #14 on: June 13, 2009, 07:38:07 PM »
Quote from: paulages on June 13, 2009, 07:20:58 PM
Quote from: bwaller on June 13, 2009, 05:27:53 PM
It's a good thing you pulled the pan.

i'll be pulling the pan every oil change on this engine for a while. the pain in doing this is that i have to pull the exhaust to do so. i'm headed down there now to pull the cam cover and inspect the chain, but i'm expecting to have to start tearing it back down this week. at least i can leave the cylinders alone, but i'll have to split the cases, split the rods, and re-time the cam upon reassembly. not how i pictured my first week with the bike after returning... could have been worse though.
You don't have to split the rods.
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Offline 754

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Re: hyvo cam chain failure on the 718??
« Reply #15 on: June 13, 2009, 07:44:34 PM »
..unless you want to leave the rings & pistons in the bores..
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #16 on: June 13, 2009, 07:54:55 PM »
Quote from: 754 on June 13, 2009, 07:44:34 PM
..unless you want to leave the rings & pistons in the bores..

that's the idea... i figure i have to split the cases either way, and i think it's easier to split the rods and pull the chain out the bottom than pull the pistons from the bores and have to refit them. that way i don't have to buy a new head gasket, etc. i can leave the head bolts torqued. i'm pretty sure i can score the timing mark accurately enough to not have to break out the dial gauge and timing wheel as well. as a matter of fact, i'm pretty sure i marked it after timing the cam the first time.

they're new rods bolts anyway, so an extra stretch probably won't kill them. the question is: buy another OEM cam chain or use the spare i have that came out of the 3000 mile engine? can't say the last chain put up much of an argument in favor of a new one being safer....
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Offline bill440cars

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Re: hyvo cam chain failure on the 718??
« Reply #17 on: June 13, 2009, 08:06:00 PM »


      Hey Paul, good to see you back! ;) Too bad about that chain, but, like has been said, glad you found it before that sucker came apart Big Time! :)


                                   Take care, Bill ;)
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #18 on: June 13, 2009, 09:39:47 PM »
Just pulled the cam cover, spun the engine through, and found the offending link. It looks like a master link clip came off and the link itself just hadn't come loose yet... except that the chain was riveted. Wow, I got lucky.

Anyway, the engine is stripped and ready to pull. If I had a new cam chain I could have it replaced and back together tomorrow afternoon. Guess I have to decide whether or not to use the older one I have.
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paul
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Offline paulages

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Re: hyvo cam chain failure on the 718??
« Reply #19 on: June 14, 2009, 03:33:09 PM »
Well, she's apart and the new chain installed. Just gotta fit the cases ans put the engine back in the frame. Frank (754) suggested that I find a chain stake and just restake the bad rivet, but I decided I didn't feel comfortable trusting myself to stake it properly after it failed to begin with. Interestingly, the failed rivet looks like it may have been where the factory joined the chain. one of the rivets ends looked different than the others, with a slight slot in the end.

Anyway, I ought to have it back up and running this evening.
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paul
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