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Suddenly a strange engine rattle noise

All the paper from Yamaha says it is 2008 year model, i know more here in sweden that's from '08 and have the silver engine. They are registered and limited as 78HP and the black S2 model is 89HP engine. :)

It is just a throttle limited to 78HP from 89HP.. :thumbup:


You mean 98Hp right??? cause the s2 engine makes 98hp:rockon:
 
It sounds like KLR with the cam journals gone bad (oiling issues).

I don't think it the CCT but you can pull that cover off and take a peek. With the noise its making, itf the chain/tensioner is at fault, you should see some new shiney aluminum where the chain removed some case...

An easy check to do, pull the oil fill plug and look inside, you'll see the clutch. Wrap some tape around the upper end of a screwdriver (so you don't tear up the threaded hole) and then put some pressure on the clutch basket itself. Push it forward/backward/in and out.. There shouldn't be ANY SLOP again...

Loss of oil pressure would cause major noise as well and can be checked but you need a gauge and an adapter to access the hole on the right side. The oil pump is chain driven.

Pullling the oil pan isn't terribly difficult (the header is the hardest part) and may very well give some insight on what failed/is failing...

*Listening to your recording again, I'm leaning towards the clutch assembly. There should be a bushing and a needle bearing that supports the entire clutch basket(under the outer basket with the fingers). Should that have excessive wear, the basket is going to flop about and scruff up the cases and make a whole bunch of noise..

As FinalImpact stated, go about the bike with a screwdriver/dowel, stethescope and see if you can narrow down the area. Look closely inside the clutch cover as stated before and put some pressure on the basket. As bad as it sounds, if its the basket, it should be pretty noticable..

Good luck...
 
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Sounds just like the cam chain. I would suspect the Cam Chain Tensioner. Replace the CCT. I would inspect the cam chain guides as well. Your bike is an 08 with the S1 speedo?

Agree! But sound like it jump a tooth on the cam and the piston are touching the valves a bit... Pop the side cover and valve cover off and check the timing mark right away... don't start the bike until you find WTF is going on there! Did you over rev? (Downshift too quick...?)

Good luck Bro!

If not try to go up/down gears... might be stuck between 2 gears and the dog ring are rubbing on each other. But my piston vs. valve theory is what I think is going on...
 
All the paper from Yamaha says it is 2008 year model, i know more here in sweden that's from '08 and have the silver engine. They are registered and limited as 78HP and the black S2 model is 89HP engine. :)

It is just a throttle limited to 78HP from 89HP.. :thumbup:

Nop! They're called FZ6R... :BLAA:

Mine is more like about 82 WHP... LOL
 
Agree! But sound like it jump a tooth on the cam and the piston are touching the valves a bit... Pop the side cover and valve cover off and check the timing mark right away... don't start the bike until you find WTF is going on there! Did you over rev? (Downshift too quick...?)

Good luck Bro!

If not try to go up/down gears... might be stuck between 2 gears and the dog ring are rubbing on each other. But my piston vs. valve theory is what I think is going on...

What I think I'm hearing is backlash off the cam chain. As the links speed up they have enough slack and inertia gather, change path and rub on another part. I would suspect the cam chain tensioner and or chain guide has failed and there is no pressure to keep slack out of the cam chain. I think if it jumped a tooth there would be idle change and change of throttle response but that seems to not be the case yet.

I agree do not run this motor until the issued has been resolved.
 
What I think I'm hearing is backlash off the cam chain. As the links speed up they have enough slack and inertia gather, change path and rub on another part. I would suspect the cam chain tensioner and or chain guide has failed and there is no pressure to keep slack out of the cam chain. I think if it jumped a tooth there would be idle change and change of throttle response but that seems to not be the case yet.

I agree do not run this motor until the issued has been resolved.

Well, when I did my cam swap I tried to go max overlap with the exhaust cam... that's how I learn about this noise... :spank: It wasn't enough to bend anything but the piston were a little too close... let's say! I had to back it off few degree. I couldn't feel anything turning the engine by hand but scare the $hit out of me when I started it!!! :eek:

There's definitely something wrong there that need to be taking care off. Revving it up and the kickstand won't fix it.
 
Nop! They're called FZ6R... :BLAA:

Mine is more like about 82 WHP... LOL

In Europe there aren't such model as FZ6R, only in US i believe or perhaps Asia too. We have only FZ6 S1 and S2 model and from 2010 there is new model XJ6..
 
What I think I'm hearing is backlash off the cam chain. As the links speed up they have enough slack and inertia gather, change path and rub on another part. I would suspect the cam chain tensioner and or chain guide has failed and there is no pressure to keep slack out of the cam chain. I think if it jumped a tooth there would be idle change and change of throttle response but that seems to not be the case yet.

I agree do not run this motor until the issued has been resolved.

Its easy enough to remove the cam chain cover and if anything has failed inside, it should be pretty obvious due to the severity of the noise.
 
What I think I'm hearing is backlash off the cam chain. As the links speed up they have enough slack and inertia gather, change path and rub on another part. I would suspect the cam chain tensioner and or chain guide has failed and there is no pressure to keep slack out of the cam chain. I think if it jumped a tooth there would be idle change and change of throttle response but that seems to not be the case yet.

I agree do not run this motor until the issued has been resolved.

I will see when the manual APE CCT has arrived if that will do any difference at all, haven't got time to check and see where the sound is coming from. Will try do that tomorrow.

It doesnt' seem to stuck between gears, it was running as usual except the sound when I was one my way back home from the evening ride.
 
How's coolant level? Was thinking of cavitation at the pump but sounds pretty bad.

As i've mentioned before, everything is like it have always been. Same temp, same preformance.. everything is like normal execpt the sound. :confused:
 
Repeat post. . .
Next step for me is to pull the oil filter and cut it open. Drain the engine oil into a clean pan and look and see if you find a snap ring, a locater /alignment pin, or any small bit that one doesn't expect to find.
It can be tough to cut an oil filter open but sometimes it needs to be done to see what's going on. Take your time and when open pull it apart an look through all of the pleats for larger debris and then lets make a best guess.

As for the starter; it just sounds like something is dragging like it ate thrust washer from either the trans or the starer area.

Are you up for pulling the side cases off to inspect this or do you have a friend who can help?
 
Well, when I did my cam swap I tried to go max overlap with the exhaust cam... that's how I learn about this noise... :spank: It wasn't enough to bend anything but the piston were a little too close... let's say! I had to back it off few degree. I couldn't feel anything turning the engine by hand but scare the $hit out of me when I started it!!! :eek:

There's definitely something wrong there that need to be taking care off. Revving it up and the kickstand won't fix it.

Once the valve timing is off is alters the burn, intake, exhaust sounds. Contact is contact and valves don't like it.

Back on topic; chains like to be pulled and during acceleration all is well as the crank is pulling the chain down towards it keeping the straight or tensioned side taught as is the space between the cams. Its at idle/steady state RPMs and during deceleration that bad things happen with loose chains. If I had to guess, a chain making that much noise would have this thing in jeopardy.

My vote is it's something else. Looking at the oil filter will likely show bits of some kind. Aluminum means something mowed down the block. Plastic means something chowed on the chain guides or some other plastic bits like the ignition P/U trigger. But it still runs good so I'm going to say it didn't do a Vegas and eat the ignition pick up coil. When you find metallic bits that are not magnetic one looks at main and connecting rod bearings as they are lead, copper, and other materials. Snap rings come the transmission as do allot of other thrust bearings and hardened materials. Chunks of gears gear box.

Lots to be gained by looking at the drippings in the oil pan. . .


If you do fire it up a record the sound with the CLUTCH IN, CLUTCH OUT, and with it IN GEAR - Clutch in. Maybe even center stand in gear too. Then drain the oil and look at it.
 
You might just be on to something there, and makes me think to myself "damn why didn't I think of that" lol
I was thinking maybe the seat cover stitching was coming loose ,but the muffler bearing is probably it..... come to think of have you greased the Flux Capacitor lately? :thumbup: :rockon:
 
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