Cam Chain Noise

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OrangevaleFJR

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I noticed my bike was making a noise coming from low in the engine. It didn't sound like the tickers I have heard. Mechanic tried tightening the cam chain and it seemed to quiet it a bit. He thinks new cam chain & sprocket is a good idea and should solve the problem. This is the same mechanic that has repaired 6 tickers and he agrees it sounds very different.

Anyone have this issue before?

 
I noticed my bike was making a noise coming from low in the engine. It didn't sound like the tickers I have heard. Mechanic tried tightening the cam chain and it seemed to quiet it a bit. He thinks new cam chain & sprocket is a good idea and should solve the problem. This is the same mechanic that has repaired 6 tickers and he agrees it sounds very different.
Anyone have this issue before?
I recall a few folks replacing the cam chain tensioner to quiet a noise from the right side. I would not expect the chain and sprocket to need replacing on a well maintained bike.

 
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I noticed my bike was making a noise coming from low in the engine. It didn't sound like the tickers I have heard. Mechanic tried tightening the cam chain and it seemed to quiet it a bit. He thinks new cam chain & sprocket is a good idea and should solve the problem. This is the same mechanic that has repaired 6 tickers and he agrees it sounds very different.
Anyone have this issue before?

Skooter had his replace on his 04. It was right before the IBR, and was covered by his YES. IIRC the bike had over 100,000 on the clock. I would shoot his a PM.... Smitty

 
More info please. Really Andrew, is 'making a noise' as descriptive as you could get? Usually we have no shortage of verbage from you. :p

Oh, and what about your FJR's mileage?

Here's my soap opera:

My engine was 'making a noise'. Coming from lower right side of engine. I described it as a 'knock' - kind of like pinging, though that wasn't exactly accurate but the best I could do. A tech described it as a 'rattle'. Once again, not perfect, but perhaps closer than my description. This noise would only occur just a tick above idle speed. Usually after goosing the throttle as it was coming back down to idle speed.

I had this noise for a while, and it slowly became worse (louder), and more consistent. But wasn't always there. I wasn't too concerned about it until that welsh wanker Skyway one day says, "what the fuck is that noise coming from your engine?" Well, now I started to get freaked and obsessive about it. I suspected it was a slack cam chain banging against something because of a bad tensioner failing to do it's job. I know of several high mileage FJRs that had a bad cam chain tensioner replaced.

Well, the rest is a long, convoluted story, so I will try to provide the Cliff Notes version.

A stop at one dealer while traveling verified it was a cam chain/tensioner issue of some sort because while the engine was running and making the noise, the tech used a screwdriver to manually add tension to the tensioner and the noise disappeared.

A short time later when home I took my FJR to a local 5 star Yamaha dealer I have never been to before but I heard good things about. In the end, I wasn't completely impressed. His diagnosis after listening to my noise and seeing I had 110,000 miles on the clock was a 'stretched cam chain'. Didn't even bother to open it up. This $18 part (can you beleive that?) was on back order. After talking with the tech one day, I also convinced him to order a new tensioner, explaining it was a common for it needing to be replaced on higher mileage FJRs. Thankfully, he listened to me and did order it. Personally, I still think there is an excellent chance it was just a bad tensioner causing my problems. This guy was young, but friendly, willing to take the time to talk to me, and seemed competent. BTW, I learned this dealership (large one) had never sold an FJR at all and had never seen one in the service department before. They were enthralled by all my farkles.

Anywho, he replaced everything in one shot: New cam chain, new guides, and new tensioner. And for the great news: EVERYTHING was covered under my 4 year Y.E.S extended warranty. Results: noise gone. :yahoo:

However, a new noise appeared. :angry2: A high pitched buzz. After the tech called Yammie corporate technical assistance the verdict was the new cam chain mating to the sprockets was causing the noise and it wasn't a prolbem. Didn't make me feel very good at the time, but that new buzz didn't last long and now 21,000 miles later so far everything is ok-dokie.

I asked him prior to the repair why the sprockets weren't being changed with the chain, he replied that it wasn't necessary, apparently verified by Yammie technical assistance. I am no expert, but I would have felt better with new sprockets. Still, so far everything is ok.

As I said, there is more to this, but most of it is whining about the dealer's customer service.

So, how would you describe the noise? Is it coming from the lower right of the engine (behind the cam chain cover) approximately?

The tech should know how to perform the simple procedure of removing the little rubber cover on the right side of the frame, inserting a really long phillips screwdriver, and manually adding tension to the tensioner. If this makes the noise go away, that tells you a lot.

The FIRST thing I would suspect is the cam chain TENSIONER. That should be the first thing replaced. For several folks, that was all that needed to be done. If the chain is replaced, also get the tensioner replaced. (It's not an easy job due to it's location near the frame) I am interested in hearing from the experts what the predominant good practice is for changing the cam chain/sprockets as a set vs. just changing the cam chain.

Good luck Andrew.

 
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Think Ion's problem was his chain tensioner had failed and let the noise go too long and the chain slipped a couple teeth and then the engine tried to consume itself, valves slamming into pistons etc. Not good. Get it fixed. PM. <>< :blink:

 
I had "the tick", had it repaired under the YES, started hearing it ~16,000, convinced the dealer at ~30,000. That was done in November last year. In the spring (I ride all year) after a couple thousand more miles, started hearing a new noise, & thought cam chain tensioner, but apparently I was the only one that could hear it then. My YES was running out in September (P.O. got a 3 year instead of 4) so I wanted to figure this out before then. It was getting louder as miles passed so waited & 6000 miles later they could hear it! Opened it up & found the timing chain was stretched. Cam chain & tensioner were fine. Replaced the timing chain on their dime & all is well w/the world. Even got a loner bike till they were done! So there are other possibilities.

 
Opened it up & found the timing chain was stretched. Cam chain & tensioner were fine.
Huh?!?!?

Unless I am completely fucked up............. well, we all know I am completely fucked up, but I digress..............

There is no such thing as a timing chain in the FJR's engine. That IS the cam chain. So, please, clarify. Have any part #s from the work order?

And how did they determine the chain was stretched? My tech told me there was no real way to measure it and find out unless it was waaaay out of spec and obvious. Not that the tech knows everything and was talking out of his ass, but if there is a way, I would like to know how they accurately measure and determine if a cam chain is within spec.

 
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I am interested in hearing from the experts what the predominant good practice is for changing the cam chain/sprockets as a set vs. just changing the cam chain.
I believe Ion stated that the sprocket on the crank is fitted in such a way that the entire assembly would need to be changed out and the costs were prohibitive. Don't know how the cam sprocket is addressed.

Capt. Bob

 
I believe Ion stated that the sprocket on the crank is fitted in such a way that the entire assembly would need to be changed out and the costs were prohibitive. Don't know how the cam sprocket is addressed.
Thanks for the info.

Sprockets on the cams are bolt-on jobbies so I do believe they would be relatively cheap and easy to swap out.

I need to take a gander over to ionbeam's thread and get caught up.

 
Read it, for sure, but I think he said one was a "pressed on" fit. I'm too lazy to go back and read it.

 
Opened it up & found the timing chain was stretched. Cam chain & tensioner were fine.
Huh?!?!?

Unless I am completely fucked up............. well, we all know I am completely fucked up, but I digress..............
I've been told never to argue with a crazy person, but I don't always do as I'm told. And, as it turns out, I'm not arguing. For some reason, the mechanic kept calling it the timing chain. It was the cam chain. And I'm tired. Sorry. But they did contact Yamaha & came to that determination. Specifically said it wasn't the tensioner and looking at the parts list they did not change it. Time for bed.

 
I'm a bit late coming to this thread, left coast hrs vs right coast hrs (and a little ball game that was going on).

Skoot's description of his cam chain noise seems to be pretty much typical of how it sounds. In my case I could see my tach wander in sync with the heavier noises. My cam chain noises started at a very young 20k mile and ended in a grenaded engine at 40k miles. I can positively say that there is the potential for a bad outcome :glare: if not taken care of.

My mechanic described what he feels is a design shortcoming with the FJR cam chain tensioner, details here. Once my engine was apart we found that my cam chain tensioner was fully extended and locked in place, but obviously it wasn't at some point. I hope to be able to autopsy the CCT once the dust settles, I expect to find damaged ratchet teeth.

The sprocket on the crank shaft that drives the cam chain is pressed on and is not replaceable. The crank shaft with the sprocket is $500 alone. The two sprockets on the cam shafts are replaceable.

FWIW, my cam chain was very worn, and the crank sprocket appears to be worn, exact measurements to happen next week. In a major shock, the cam chain was still in place, the CCT was extended, the two chain slippers were in place, the cam sprockets looked new, and the chain was over both cam sprockets. The cams were pretty much locked in place by all the bent and wedged mechanical parts in the cylinder head. When the engine was cranked by hand, the crank sprocket would spin but the cam chain simply skipped along the gear teeth with out turning. The mechanic started recounting his considerable years of experience and how this was another first for him to see.

I believe my 'failure' is unique but it shows that if you are hearing noises it behooves you to get the cam chain system serviced. The cam chain is ~$16, the tensioner is ~$70, and in perhaps a telling way, the cam chains are on back-order, kinda like there is an unexpected consumption.

There is no such thing as a timing chain in the FJR's engine. That IS the cam chain. So, please, clarify. Have any part #s from the work order?
The engine has spark timing and mechanical timing.

There is a second gear just on the outside of the crank shaft sprocket (that drives the cam chain) which is used to determine absolute crank shaft position. The output of the sensor that reads this gear is used as the base signal from which spark timing is calculated by the ECU.

Mechanical timing is the relationship of the crank shaft angle vs the position of the valves. There is a specific procedure that aligns the crank shaft cam chain gear with the two cam gears which ensures the reciprocating parts of the engine are in synch with each other.

My 'worn' cam chain isn't about stretch (length), it is about the condition of the chain links which compromises the chain's fit over the sprocket's teeth. The crank sprocket is a 2:1 ratio with the cam sprockets (crank sprocket 1/2 the dia of the cam sprockets) and the crank sprocket is driven vs the cams following. It was at the crank sprocket where the worn chain failed to engage sufficiently. The sprocket/chain fit or lack of, was most likely exacerbated by the Cam Chain Tensioner allowing a brief moment of slack.

 
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The cam chain controls the timing relationship between the intake and exhaust cams, as well as the overall cam timing. As the chain ages it does "stretch" a bit. This induces a timing change (between the intake and exhaust cams) of 2-3 degrees in the typical "worn" Yamaha cam chain. In racing bikes, the 3 degree change is monumental. I doubt you would notice it much on a FJR unless you frequent the 8k rpm range (and we don't know anybody who does, right?).

Assuming an overall average traveling speed of 50 mph, an FJR with 100,000 miles on it also has 2,000 hours. That's a shitload of hours on any cam chain! In most of my Yamaha racing bikes, I replace the cam chain every 200 hours, but typically sell the bike before the tensioner ever needs changing.

If at all possible, I would always want to replace the cam chain when replacing the tensioner. By the time the typical tensioner is worn/weak, the cam chain has already been subjected to a lot of slack running, flopping around etc., and is bound to be worn.

It is typical and customary, NOT to replace the gears. And the noise made for a bit, while a new cam chain "seats" on moderately worn gears is normal.

I just realized as I came back to edit this post, that I am publicly posting how I get about 5% more horsepower on a one year old racing bike than my typical competitor, and I only spend $18 on a cam chain to do it!

:(

Inserted for your viewing pleasure:

Camshaft-1.gif


The intake and exhaust cam gears do NOT engage each other. They are both driven independently by the cam chain. So you can easily see how any stretch of the cam chain causes a change in the timing relationship between the two cams.

Motto of this tale... Change your damn oil! And before your YES warranty runs out, get a dealer to hear a noise coming from the right side so Yamaha pays for replacing your tensioner and cam chain.

:)

 
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Yea, IonBeam did.............. CHANGE IT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
https://www.fjrforum.com/forum//index.php?showtopic=26889
whoa...thanks Rogue...CCT scheduled for replacement and cam chain scheduled for check. Interestingly enough, the noise started at 39k miles. Was mild, figured bike was getting worn in...now it's worse.

So the bike now has 40k miles. At idle, from low on the engine, but above tranny, there is a noise that sounds like a chain being drug in a flopping manner/rattling along the inside of the engine, at RPM, the noise goes away it seems. The noise is similar to a diesel clanking away. The noise is loudest from the right side, but also on the left.

Yep, the tech tightened the tensioner and it reduced the noise a bit, but no a lot. I am going to ask for a new CCT, Chain and not the irreplaceable sprocket. :)

Thanks for the advice, links, history, and stuff.

sniff...sniff...my first mechanical issue with the FJR and you all have helped me a lot. Sniff.

 
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FWIW, my cam chain was very worn, and the crank sprocket appears to be worn, exact measurements to happen next week. In a major shock, the cam chain was still in place, the CCT was extended, the two chain slippers were in place, the cam sprockets looked new, and the chain was over both cam sprockets. The cams were pretty much locked in place by all the bent and wedged mechanical parts in the cylinder head. When the engine was cranked by hand, the crank sprocket would spin but the cam chain simply skipped along the gear teeth with out turning. The mechanic started recounting his considerable years of experience and how this was another first for him to see.
I believe my 'failure' is unique but it shows that if you are hearing noises it behooves you to get the cam chain system serviced. The cam chain is ~$16, the tensioner is ~$70, and in perhaps a telling way, the cam chains are on back-order, kinda like there is an unexpected consumption.
Chains and sprockets normally wear (and wear out) together. If the crank sprocket and chain were badly worn but the cam sprockets looked new, could it be possible that the root cause of this failure was the crank sprocket rather than the cam chain system?

 
<snip>The sprocket on the crank shaft that drives the cam chain is pressed on and is not replaceable. The crank shaft with the sprocket is $500 alone. The two sprockets on the cam shafts are replaceable. FWIW, my cam chain was very worn, and the crank sprocket appears to be worn, exact measurements to happen next week. ....the crank sprocket would spin but the cam chain simply skipped along the gear teeth with out turning. The mechanic started recounting his considerable years of experience and how this was another first for him to see.

My 'worn' cam chain isn't about stretch (length), it is about the condition of the chain links which compromises the chain's fit over the sprocket's teeth. The sprocket/chain fit or lack of, was most likely exacerbated by the Cam Chain Tensioner allowing a brief moment of slack.
SkooterG: And how did they determine the chain was stretched? My tech told me there was no real way to measure it...
Unfortunately, recounting my considerable years of experience, it is not the first incidence and I've purchased several crankshafts w/fixed cam drive sprockets -- sucks.... The reason, I believe, is incorrect/insufficient hardening at the factory. In some cases, all of the other corresponding cam drive parts are fine -- except for that damn sprocket. I've never succeeded in getting an admission of fault by any company -- pay-up sucker!

In answer to SkooterG's question: yes, cam chain length/stretch can be determined by accurately measuring the pin-to-pin distance (chain pitch). This was/is quite common for roller chains (like, drive chains) but is hardly an issue for Hy-Vo (multi-plate) style chains. Chain 'stretch' is actually a measure of the accumulated wear in all the moving parts.

Unfortunately for Ionbeam it appears he's fallen victim to another of Yamaha's metallurgy problems -- like the infamous valve stem/valve guide interface issue.

Good luck -- with a good automotive machine shop (race engine shop) things can, often, be made right again.

All one needs is $$$.....

 
Not to beat a dead horse here, nor start a whole new round of NEPRT style postings, but now you know why I change my oil far too often. Hy-Vo chains can go literally forever when kept happy with lots o good clean lube, and a tensioner that does what it's name implies.

 
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