Metallic Noise - Timing Chain or Transmission?

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RavFJR

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I have a 2009 with 27,000 miles on it and just had to replace the CCT. Pulled the Blue dot CCT out to find it had a broken spring. Replaced it with a Green dot CCT and the 'marbles in a can' noise went away. However, I now have a constant metallic noise going on... Sounds sort of like a timing cam chain that isn't getting any lubrication. The noise is noticeable at any RPM, but more pronounced at idle. I can hear the noise on both sides of the bike. I'm wondering if the old CCT could have damaged the chain, or it's something to do with the transmission? Other than the noise, the bike runs great... Does anyone have any ideas?

 
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If it wasn't there prior to your repair i suggest looking at it again.

Dave

 
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Man that sucks. For some reason I thought the 09's had the green dot from factory. When I had valves checked I told the dealer to check my tensioner and replace it if blue. My bike is an 09. He said mine was okay, no replacement needed. Hope it all works out for ya.

 
Man that sucks. For some reason I thought the 09's had the green dot from factory. When I had valves checked I told the dealer to check my tensioner and replace it if blue. My bike is an 09. He said mine was okay, no replacement needed. Hope it all works out for ya.
I don't know if there is a difference between the blue dot and the green dot cam chain tensioners.  The big issue was with the pre-blue dot tensioners.  The updated (blue dot) tensioners were used by the factory starting sometime late in the 2007 model year.  My 2007 had the old style which I replaced at maybe 30,000 miles or so.  (No noises or issues; just preventative service)

 
Repair shop reported that chain had stretched beyond specs. Said I was lucky it didn't jump a (sprocket) tooth. Was going to wait until after riding season to do the valve check myself, but since the shop is replacing the chain, having them do the valve check as well. The shop said that Yamaha has had tensioner issues with several of their model bikes. I'm just happy I didn't  trash the top-end.

 
Stretched beyond specs?  I couldn't find any specifications in the FSM - perhaps they have another document for this information.

 
 I was told they checked the slack on the chain at tension and found it unacceptable. I used the term 'spec' loosely  to note that the chain was stretched - not nominal. My apologies for inferring it was a specific measurement. I'm sure there is a way to check tolerances, but I do not know how this is done. 

Currently,  they are waiting for a new chain to show up to install. They are also doing the valve check. I'll wait until the bike is done to offer any other issues the shop might have found.

 
What do you mean, "Broken spring?" As in, the spring actually broke and was in pieces, or it was just tired and wasn't giving proper tension?

The latter has been pretty common with pre-2007 bikes. If it was broken-broken, I think that would be a first.

 
What do you mean, "Broken spring?" As in, the spring actually broke and was in pieces, or it was just tired and wasn't giving proper tension?

The latter has been pretty common with pre-2007 bikes. If it was broken-broken, I think that would be a first.
Broken as it wouldn't hold proper tension. Talking to the shop, I will be going to a manual tensioner. After talking to the service manager about his experiences with self adjusting tensioner problems, it seems the best solution.

 
Update on the bike... Valve check revealed 3 valves out of spec (2 exhaust, 1 intake). Cam chain replacement found elongated sections on the old chain. Bike is still at the shop because the tow service damaged my paint during transport, and the shop has a painting service.  Tow service will be paying for this repair. 

Had the OEM auto adjust CCT replaced with a manual CCT. I determined a manual CCT to be the most reliable way to go. The shop said that auto adjust CCTs aren't up to the task of high revving sport bike type engines,  and they get quite a few of (all model) bikes in for repair because of CCT failures.

After discussion with the shop and research, in a nutshell found that engine heat weakens the CCT spring, and that the high engine RPM demands (both accel and decel) over tax the auto CCT mechanism. I'm just sharing my motivation to the direction I took after doing the research. It's up to each person to do what they believe works best for them.

 
I don't like your shop.  I am just seeing this thread, but I sure as heck would like to know how a 29k mile FJR has an elongated cam chain?  There are tons of 100k and 200k mile FJRs out there with their original cam chain.  My BS meter is pegged.

Ditto for the manual cam chain tensioner.  There's nothing wrong with going to one, though I wouldn't for the PITA aspect of having to manually adjust, but for them to say that the OEM self-tensioning CCT is not up to the task is a giant pile of crap.  Once again, plenty of 100k, 200k FJRs out there with their OEM CCT running just fine.

But if you are happy, that is all that matters.

 
^^^^^^^^^ Agreed !

That cam chain is a multi-plate 'silent' design which is way overbuilt for the stress it sees driving those cam sprockets - in a clean, oily environment. Chains Do Not Stretch, their pins wear out due to lack of lubrication. I do not see that happening inside this engine. Since the shop did replace the cam chain, ask for it back. Measure 25 pins worth of stretched length. Take this measurement on any length of this chain at random. I doubt there will be any measurable variation outside of the accuracy and repeatability of your method. Have a look at the teeth on the cam sprockets, on the crank shaft sprocket, you will not find much wear after the initial break in marking. Look at the underside of the chain 'teeth' where it rides on the sprockets.

Reading the original post, I would be more inclined to look at the cam chain guides. If they are worn beyond a certain point the tensioner may not have enough stroke to properly take up the slack. What does the oil look like, was the oil filter opened up to have a look at what it strained out? The offending noise was reported coming from both sides of the engine, the cam chain is on the far right side. Did a mechanic use a sounding stick to try to pinpoint where this noise was coming from? Is the bike back together? Is the noise gone now? 

I'm with Scooter on this one, the BS banner is flying high with me too! Me thinks this shop is making work for themselves. - BUT, that's just my HUMBLE opinion.

I'm the one who contacted American Performance Engineering way back in '07 to have them look into our issue. After supplying them with the necessary information they sent me a prototype to try on my '06 AE. I cut off the welded double nuts, hack sawed a screw driver slot, installed and ran it for several years. They also gave me one of the first production parts. It works as advertised, however, you have to make periodic adjustments, which most people have no clue how to do. It is very possible to do damage by running a manual cam tensioner too tight! About 7 years ago I had enough and put in the redesigned blue dot OEM unit. My '08 is running the current green dot OEM unit. It works well, and is out of sight - out of mind. So far, at 90K miles on the odometer, there is no loose cam chain noise at all.

Of course, Your Mileage May Vary.

Brodie

😏

 
^^^

I agree with Brodie and Skooter.  Chains don't stretch and the (apparent?) failure of the OP's blue-dot CCT is the first I have ever heard of - nonsense to say that auto-adjusting CCT can't handle the FJR's rather modest max RPM.  (Maybe this one was defective?)  While the pins can wear resulting in apparent elongation of a chain, I wouldn't expect to see much on a low mileage FJR - too many 200,000+ mile ones out there working perfectly well.  

If I am wrong (I think it may have happened once or twice), the shop had better replace the cam sprockets along with the chain.  If the chain is anything like they claim then the sprockets are toast.  Not so easy to replace the sprocket on the crank.

 
Read the posts and I will request the old chain, which i hope wasn't' discarded. I can say that the old chain was making a awful noise, even after the green dot CCT was installed. Bike is still at the shop dealing with the paint problem.

Update: Just got off the phone with the shop and they will show me the old chain, and confirmed that it had stretched. Confirmed that the sprockets and guides look good. As far as using a manual CCT, just my preference. Bike Tupperware is going to the paint booth tomorrow, and I was promised the bike back on Friday, October 4th. When I pick up the bike I plan to talk the to mechanic about the details of the work that was performed. I will be happy if the bike is quiet and I can start riding again.

 
Good luck.  I hope it works out for you. 

Difficult to diagnose via web forum although we all do it.  Still, there is a tremendous collective experience and knowledge here.

I will be very interested in seeing some chain measurements i.e. length of a section of a certain number of links (pulled tight) of the "worn" chain vs a new one.  Still don't get their opinion on the CCT.  I would never opt for a manual one.  I would be afraid of setting it too tight or too loose (or forgetting to check it at all).

 
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