Clutch release knock!


After releasing the clutch lever i can hear a knock coming from the bottom of the bike. Can any one tell me what it could be.
Only one thing that I can think of. On an old dirt bike I had once the chain and sprockets were worn out it would make noises. The chain wasn't rolling off the front sprocket teeth the way is should. But it was noisy the hole time. Just something to look at.
Its the rubber cushion in the drive between the back sprocket and the wheel hub. Mine drove me nuts at first till I found out what it was. Its the slack being taken up just as you let out the cluch and the bike just starts to move.
It seems like you're getting the wrong answers.

You are probably hearing the noise when in neutral at a stop.

The noise is in the engine and not in the rear sprocket area.

The noise you are hearing is normal and should not worry you.

My Busa has it too and my old KZ1000 Kawasaki is really loud too.
Busa Prime I know what your talking about my friends 2000 Busa makes the noise your writing about when in neutral. I think Max speed hit it on the nose because it is when it's in gear, then I release the lever and nock!, but thanks anyway
I have had to replace my cush drive pads because I didnt make certain they were properly set in place after I changed my first rear tire.But I also have this noise your talking about on my 2000 and it sounds to me like it is coming from the bottom of the bike.
Sorry I answered your question wrong GIO.

When I read your post you didn't mention you were just rolling out after releasing the clutch.

I assumed you were in neutral. :hammerhead:
Doug S.

Let us know exactly what knock you are hearing coming from the bottom of your Busa.

Let me know the conditions exactly when you hear it.

My bike has a slight knock after you drive it for a while like any where between 5 and 30 miles at a steady speed like highway speeds and then you slow down for a stop.

You hear it when you lightly rev the engine from idle up to 1500rpms or 2000rpms .

Sound like a light piston pin knock or piston skirt slap type of sound. After the bike has been in stop and go city driving it seems to lessen or go away altogether until I go for steady freeway driving of 20 miles or so.

You never hear it above 2000rpm. When you hear it you can also feel it thru the handlebars or frame. I ruled out bearings since I never hear it above that rpms and I have 7500 miles on my Busa.

I have a case number from Suzuki regarding this noise but the dealer said there is nothing wrong.

I'm keeping a close ear on the noise. It has never been any louder or worse than when I first noticed it.

Busa Prime,

Sorry for the lack of info on the nock! The dealer mechanic told me the same they told you, that it was normal. He told me that the busas come with a delay in the trans so you wont get as much tire slip. I don't know how that has to do anything with the nock. I don't know who to trust anymore.

I've asked 4 different bike mechanics about hooking up a shift light on my Busa and they gave me 4 different answers. The damn light still does'nt work. That's why I have the lack of trust for bike mechanics.

My 99 seems to have the same problem described in the first post. the clunk happens just as the clutch fully engages as if something in the throwout fork is catching on something. I feel it in the shifter. It does NOT happen all the time and only happens when i have come to a complete stop and then take off relatively slowly. i have not noticed it when i have shifted from neutral to first. only after coming down from second to first and stop with the clutch in. If it was a mechanical clutch i would almost swear it was something in the cam at the throwout fork. It may be that it is the rear hub cushions. the dealer who replaced the brake rotor that got eaten by a caliper that froze, did a piss poor job of putting things back together( never adjusted the chain or bled the brakes or even locked down the chain tensioners). I will have to watch and see if the chain jumps at all. It feels like it is in the clutch housing tho. any help would be appreciated.........
Sounds like the back torque limiter in the clutch. It's supposed to help prevent wheelslip during downshifts. My '02 GSXR600 had it and my '02 GSXR1000 did it too (though not as bad) I haven't heard it on my '02 busa yet. I've only got 600 miles on it though. My mechanic tells me it's normal. I've been dealing with the same people for 10 years now and they've never been wrong one any of the problems I've had. Good luck with it.
There is one other possibility you are all forgetting. You need to ask how vigorous is the clutch engagement. The Busa has a lock up style clutch. If you look carefully at the clutch parts you will see the ramps that engage to lock down the clutch so it won't slip with this much horsepower and such small surface area for a wet clutch. This sometimes will make just one momentary knoock as the clutch lever is released and the clutch locks down. In fact, on a friends Busa with Nitrous, extended swing arm, etc,...for racing, the knock was so bad that he approached me about how to damp the lockdown so it wasn't so violent because it broke the drag slicks loose as it locked up. I showed him how to machine some small round holes adjacent to the basket to insert hard urethane plugs to damp the lock down and stop the noise. If there is more than just one knock with each clutch engagement then it may be something else. If just one knock from deep in the right side of the case with each engagement it is probably the lockdown ramps engaging.
My 2001 never made this noise until I had it in for a check up. now everytime I slowly let out the clutch you hear a clunk, it is driving me crazy I just need to take it in but My dealer is a hack
I also Have had a clutch knocking sound, seems to be only when starting up from cold.It cant be anything to do with wear as the bike is a brand new K3.Also had it checked at its first 600 service and I was told that there was nothing wrong.It just seems a little odd that a new bike can make a knocking noise anyway!<span style='color:darkblue'></span>
I think I may have the same problem with my 05 Busa .It kinda roars and rattles
in neutral with the clutch out and gets quieter when I pull it in. My clutch
fluid has already turned dark with 2500 miles. I noticed with the choke on
that pulling the clutch in lowers the rpm's from 2k to 1k. When i rev the
engine in neutral from 1k to 2k (when hot) I hear the knock bad . I can feel the knock in the handlebars too. Sounds
like maybe a loose clutch basket. I've changed oil 3 times so far and have
some fillings on the magnetic drain plug each time. I've called the Suzuki dealer (Sloans) in Murfreesboro,Tn to have them look at it tommorrow. If the dealer says it's normal. I got something in writing in case it breaks later on. It's in warranty. I ride with another 05 Busa and his doesn't make any of the noises and he has the same 2500 miles. It doesn't make the noise going down the road with a load on the motor. Least I don't hear it then.
It seems like you're getting the wrong answers.

You are probably hearing the noise when in neutral at a stop.

The noise is in the engine and not in the rear sprocket area.

The noise you are hearing is normal and should not worry you.

My Busa has it too and my old KZ1000 Kawasaki is really loud too.

Reason for Edit: None given...|1151973234 -->
gio, my 05' has the same noise it seem to come frim the bottom of the bike and only when start off from a stop (not hard starts). The noise has gone away for the most part after cleaning the chain and loosen it just a little. I been to the dealer 3 times and this is the only thing that seem to work good luck!

If everyone with this problem state year and miles to see if it's related to a year.
05' LE 5000 miles.???
Re: Clutch release knock!

Had the same on my K6 Busa. Replaced the cushion rubbers at the rear hub and it was a lot better after that. What also help is that you pull and release the clutch 2 or 3 times when at stop and in neutral before you engage.

Have another noise but only when it is hot. At first it went away when I pull in the clutch but now there is no differance. If I run it for 30ks at 260 km/h it is so bad that it sounds like the bearings are badly worn. Runs quiet when it is cold.

Anybody have an idea before I allow the mechanic to strip the motor to investigate the noise?
Not sure if you have a Gen 1 or Gen 2, but the clutch bolts on the Gen2 have been known to back out and cause a grind/knock noise.

If the knock is almost like your drive train has slack in it, I would say it's the back torque limiter. As soon as I went to the billet mod mine went away. Wouldn't recommend the billet mod for a daily driver though, as your ability to use the engine to brake becomes slightly limited.

Check your chain to ensure you are adjusted correctly, and your cush drive for excessive wear....the poly replacement cush drive isn't that expensive and is way better than the stock rubber one. IMO that's the best place to start. :beerchug:
so i see this is an old as dirt post. did anyone finally get a solution to this? mine has just started doing it. no knock in neutral with revs just in gear at initial take off. I do not feel it in the shifter either as others have stated.