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Discussion Starter #1 (Edited)
Hi All
I have a strange intermittent noise coming from the engine area. Best way to describe it is that its like a rattle snake noise comes in and out intermittently on idle. I replaced the cam chain tensioner about 4k miles ago and Ive just wound it out again with a screw driver and reset it when you pull the screwdriver out, you can hear it reset against the chain. It is an automatic tensioner. Also, if I up the revs is seems to go away??? I have attached a sound file for any input you guys may have. You will have to listen carefully as it was done on my phone. The Bike has done 40k and not missed a beat so far.

Any comments would be much appreciated.

View attachment engine noise.mp3 View attachment engine noise.mp3
 

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Discussion Starter #3
Thanks Punts
Will have a look and see if I can do the adjustment myself. The best way to describe the noise as you've probably heard from the attached sound file is like a rattle snake rattling its tail intermittently.
Thanks for your help mate. I could do with some pics to help me find the adjusters, any ideas where I could find these?
Thanks gain for your help.
 

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Crj
If you look in the resources section there is a link to a factory service manual. It will give you pics and the adjustment procedure as well.
Give a holler if you get stuck. We'll be happy to help out.
 

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To help verify it's not the cam chain tensioner, play with throttle to get engine to make the noise. Then, using the same screwdriver in the tensioner, just push on it without turning. This will change the tension, and the noise. If not, move onto the next thing, which maybe the adjusters. The only other external causes I can think of would be either the water pump, or a loose stator.
 

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This might sound off the wall, but take a minute to check the drive chain condition/adjustment and sprockets. It may seem counter-intuitive, but worn drive chains can be the source of lots of assorted (and otherwise baffling) noises. Tracing an unsettling sound on a running/idling bike is often as much an art as science. Given the right vibrations (think pitch & harmonics) these slippery little audible gremlins can seem to come from components that are not really at fault. Never overlook the simple stuff. While I suppose it's within the realm of possibility that a fairly new (4K) cam chain tensioner could fail, I'd be surprised. Balance shafts suddenly becoming erratic would be equally surprising. The XX is an extremely reliable design; its OEM components are not prone to premature failure. Tracing sounds is challenging; patience and logic are your best tools.
 

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Just got a thought. Use a long screwdriver and touch at the clutch basket, the CCT and the balance shaft adjusters and see if the sound gets louder near any one of these. If it does then that's most likely your problem area.

On another note as mentioned by Fizz. Bring the rpm up to about 3000 and listen for that marble sound. then slowly increase it to 4000. The CCt's typically resonate in that rpm range so if the noise stops or drops off markedly then it's most likely your CCT.

There is a way to retention the CCT. I've done it myself and that CCT is still in there.

So step 1 turn the adjuster out until the unit locks. Remove it and then release it. Now here is the tricky part. If you look you will see a metal lock wire in a groove. Carefully use a small screw driver or pick and work it out of the groove. Note the base plate has 2 wide tabs and 2 narrow tabs. you need to carefully lift the plate up out of the notches. Now be careful the plate is under spring tension. you need to carefully lift the plate and clock it 2 more turns and reset it back into the tab reliefs. If you look at the housing there is a notch as well. This is where the springs hook sets.
Now if the plate got away from you don't panic. (Been here done this) The original setting is 10 turns from the relaxed position. So just reset the spring in the groove and carefully give it 12 turns. If the spring came completely loose then the bottom end sets in a grove across the end of the adjuster post just rest set it and start your 12 turns.
 
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Discussion Starter #8
Thanks guys for your input. I have a day off tomorrow so I'm going to go over the stuff people suggest and see what I can come up with. First off I'll whip the cans off to make sure its not a baffle or anything. Will post back here later.
 

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Weird noise for sure........ only question I have is....... did you put a new slipper blade in when you changed your cam chain and tensioner? Also, try balancing the throttle bodies as this makes the BB motor run very smooth when done right.
 

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I haven't had the change to hear how yours sounded. But the last strange rattling sound I had to deal with is that one of the bolts that holds the stator in place was loose and was scraping on the rotor off and on
 
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