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Pretty good advice over there about trying to locate the problem.

You should check over that chain really good for any links that seem out of place. Try to feel the side plates and check the rivets for any differences both by touch and sight. Clean it up real well first so you can see what's going on. And check the sprockets over really well for any bent or cracked teeth And pull the drive sprocket cover and check that the sprocket is still properley in place. The speedo pickup is also in there. Perhaps the jar from landing displaced it and now it touches the sprocket under certain conditions. Make sure you can't move the front sprocket back and forth on the shaft and check for any signs of things touching.

If the chain and sprockets check out then pull the rear wheel and look over the rubbers in the cush drive. It's so cold that just possibly one or more blocks tore or shattered and that's what is causing the noise. This ones a long shot but what the hell.

That's about all I can offer for now. Oh, and while the back wheel is off check all 3 or 4 of the rear wheel bearings for smooth rotation. Check the end faces and inner bore of the races for any sign of cracks. A broken race on a ball bearing can set up a hell of a noise.
 

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Discussion Starter #3
thanks for the advice.

I hope it's nothing.... but on a side note, Xenz 98 gsxr600 during the same day with us (i swore) made the same noise as mine when he was decelerating hard....

Xenz your bike did make the same noises as mine when you were slowing down hard before going over the rock patch right?? pleease sayy yes :) :) :)
 

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"yes" as per requested.

1. Have you adjusted your chain yet ?
2. If yes goto 3. If not adjust it first.
3. Check rear sproket for any damage tooth
4. Check chain for any damage
5. During normal riding, make sure no wierd sound comes from tranny.
6. Re-do the hard deceleration thing and listen carefully.

I adjusted my chain that night but I haven't re-do any "panic" stop after I did my chain so I can't confirm if it's because of the chain hitting the swingarm or not.

Now come to think about it, when we get panic, ok, we may have hit the rear brake, may gear down 1 or 2 shift, may grab the front brake and may grab the clutch...

Grabing the clutch won't give any sound, if you're sure you didn't hit the brake then I'll assume you didn't hit the front brake but I don't think you had pay attention to your feet. (geared down or rear brake locked)

What do you think ?
 

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Discussion Starter #6
xenz said:
"yes" as per requested.

1. Have you adjusted your chain yet ?
2. If yes goto 3. If not adjust it first.
3. Check rear sproket for any damage tooth
4. Check chain for any damage
5. During normal riding, make sure no wierd sound comes from tranny.
6. Re-do the hard deceleration thing and listen carefully.

I adjusted my chain that night but I haven't re-do any "panic" stop after I did my chain so I can't confirm if it's because of the chain hitting the swingarm or not.

Now come to think about it, when we get panic, ok, we may have hit the rear brake, may gear down 1 or 2 shift, may grab the front brake and may grab the clutch...

Grabing the clutch won't give any sound, if you're sure you didn't hit the brake then I'll assume you didn't hit the front brake but I don't think you had pay attention to your feet. (geared down or rear brake locked)

What do you think ?
The first time (when I did the wheelie) I pulled the clutch in after I landed, then I braked at the same time....

The second time, (the one you were filming) I'm pretty sure I didn't pull the clutch in when declerating, I might have been, I can't remember though.... but I was not on the front brake at all, and pretty sure I was not on the rear brake, if I was on the rear brake, it might have been very very softly, cause I was covering it when slowing down, but dont recall pressing it....

Oh, my chain was adjusted that same night at bluestones.... i'm gonna do a really hard declerating tommorrow to see if it does it again.... I was out today and did some minor hard, not as hard as before, decelerating, and had no problems.

btw, your bike did make the same clunk clunk sound that same day didn't it? i'm pretty sure it did....
 

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yes it did.

In fact it happen to me a few more times before, and they all happen when I do a super panic stop / emergency deceleration.
 

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Discussion Starter #8
phew.... I feel much better now that you said that :) I'm gonna do some tests tommorrow and see if it happens again when I decelerate hard.... gonna try it in different ways, like no clutch and brake hard, and clutch and brake hard, etc....
 

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Canadian_Gixxer said:
phew.... I feel much better now that you said that :) I'm gonna do some tests tommorrow and see if it happens again when I decelerate hard.... gonna try it in different ways, like no clutch and brake hard, and clutch and brake hard, etc....
I won't be surprise if you didn't hear any of those clunk sound again. Not that because you had adjusted the chain, but you know, when you intentionally doing such move is different then happen all of a sudden.

Do you happen to remember if you had gear down or not ?
 

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On a side note, I NEVER grab the clutch when I want to stop, there is much to be said about engine braking power.

Mind you, if your coming out of a wheelie, this may be your only choice - although I would think just closing the throttle would have the same effect.
 

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Discussion Starter #11
xenz said:


I won't be surprise if you didn't hear any of those clunk sound again. Not that because you had adjusted the chain, but you know, when you intentionally doing such move is different then happen all of a sudden.

Do you happen to remember if you had gear down or not ?
the first time when I did the wheelie, after I landed, I pulled in the clutch and braked both front and rear at the same time. I was in first gear when this happened, so I could not shift down....

the second time was kinda the same, I recall pulling the clutch in until after I started hearing the noises.... I was again in first gear the whole time....
 

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Discussion Starter #12
absolutdm said:
On a side note, I NEVER grab the clutch when I want to stop, there is much to be said about engine braking power.

Mind you, if your coming out of a wheelie, this may be your only choice - although I would think just closing the throttle would have the same effect.
Im a engine brake guy myself, but when I panic stop, I pull the clutch in and use all brake....

But what happened was, I ran the bike up to 9k in 1st gear, shut the throttle off, then wacked it open fully, the bike came up, I probably held it for 3-4 seconds, then I shit my pants cause from my perspective it seemed high, so I shut the throttle off, the bike landed kinda hard, not nearly as hard as stuff I see in stunt videos (especially from what I see people do, my landing was tame if anything, but you never know I guess), then when the front was back on the ground, I pulled the clutch in and braked both front and rear. I was full of different types of emotion, joy, happy, excited, and pain (crushed my nuts on tank when landing :( )

on the second try, I backed off, I felt a wiggle on the front end, so I didn't get the wheel up, but I braked kind hard same noise again.... I'm pretty sure I pulled clutch in after the noise started.... we had this one record on a camera, when playing it back, you can clearly hear the noise.... we just figured it was my slack on my chain (it was easily touching my swingarm when we pushed it upped), so the chain got adjusted that night.
 

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Could it be :

1. Chain hit swingarm
2. Chain slipped in front sproket

I remember one time I was doing 80click and need to do a 90degree right turn at the next intersection, gear down, decelerate hard, slow enough to do the turn. Same clunk noise came up but forgot what combination I did (front/rear/clutch/gear).

Hmm... I guess we have enough evidence/hint here, I will wait for the more experienced one to step in for a better analysis of this problem. Bruce... Lloyd... anyone ?
 

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Discussion Starter #14
xenz said:
Could it be :

1. Chain hit swingarm
2. Chain slipped in front sproket

I remember one time I was doing 80click and need to do a 90degree right turn at the next intersection, gear down, decelerate hard, slow enough to do the turn. Same clunk noise came up but forgot what combination I did (front/rear/clutch/gear).

Hmm... I guess we have enough evidence/hint here, I will wait for Mighty Bruce to step in for a better analysis of this problem.
yeah it could be panic stopping or just another strange gixxer trait or the chain slapping.... i'll do some panic stops in the london drugs parking lot tommorrow for the morning ride i'm going on, i'll post my results when I get back from it....
 

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Ya know, from reading more about this here I'm starting to think that you guys just got into some rear wheel hopping caused by the hard braking and cold shocks and tires.

Did the back end shudder up through the saddle? Or was it just a noise and the bike was otherwise smooth?
 

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Discussion Starter #16
BMatthews said:
Ya know, from reading more about this here I'm starting to think that you guys just got into some rear wheel hopping caused by the hard braking and cold shocks and tires.

Did the back end shudder up through the saddle? Or was it just a noise and the bike was otherwise smooth?
yup, I do feel some vibration shutter type thing that you just described when this happens.... not much though, but enough to notice it.
 

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BMatthews said:
Did the back end shudder up through the saddle? Or was it just a noise and the bike was otherwise smooth?
The back end do hop for a bit... that's why I was wondering about the loosen chain hitting the swingarm part.
 

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Well, in that case I'd look over the stuff as I and the others said but it's starting to sound more like you just got some back end chatter caused by braking hard on both ends at the same time. It's a sign that the rear end is almost locking up and your rear shock is set too stiff.

This is a sign of too much compression damping in the rear shock. My old 9R did this and they softened the stock settings for succeeding years.

With the cold weather your shocks are a lot stiffer than "normal" so the damping is all off as well. With the warm weather coming things will get back to normal soon.

And with TWO of you getting much the same thing I'm almost sure that's all it was. The chances that both of you broke the same way at the same time are somewhere between slim and nill.

OK, you can start breathing easier now..........
 

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Discussion Starter #19
now I can sleep soundly tonight.... I was beginning to worry.... but (knock on wood) again, i'll be checking over my bike tommorrow morning as hard as a United States Customs Guard on any foreign immagrate entering the country :)
 

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Canadian_Gixxer said:
now I can sleep soundly tonight.... I was beginning to worry.... but (knock on wood) again, i'll be checking over my bike tommorrow morning as hard as a United States Customs Guard on any foreign immagrate entering the country :)
What? :eek You're gonna stip it down and drill holes in the frame, wheels, tires and gas tank looking for drugs??????
 
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