Weird knocking..intermittently...





rashad

Registered
#1
ive searched a bunch on this but cant seem to find exactly what im experiencing.. which scares me..

My bike runs fine.. its a beast. It pulls hard. But when its up to operating temp... at a stop.. in gear or neutral, clutch in or out.. at idle (1150 ish)...

It kinda makes an intermittent soft knock/clunk sound..its not loud and at an idle of bupbupbupbupbupbup youll hear knock knock knock......nothing..then a couple again...randomly. like someone hitting the gas tank from underneath with a rubber mallet..

It almost sounds like its reverberating through the tank.. like when you go over stutter bumps and the tank makes a clunk..

I know these are noisy animals, and it has been doing it since I bought the bike.. 2.5 mos or 5000 miles ago....(yes I know I ride too much!)

Im thinking about going to Amsoil and see if it goes away.. its at idle or slightly off idle..

In fact, it gets a little worse around 1200.. then disappears...

Ideas? Oh and there are stiffer clutch springs from what i can tell. The bike was dragraced for two seasons but please dont come in and post "WELP theres your problem!" solely on that,because again, it runs absolutely fine and was pretty well maintained other than this...
 

Revolution

revolution custom paint
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#2
haa haaaa! the ol' washing machine sound. come from the cam chain tensioner. ask me how i know?...'cause i "learnt" it here on THE ORG..resistance is futile!
 

Amode

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#3
Amsoil is not going to fix your problem. Try putting a load on the motor by letting out the clutch a little bit and see if the noise goes away at idle. It sounds more like clutch probs than motor. If motor issuses it would not go away at 1200 rpm. if you change oil which i would go to a full syn racing 10 40 like mobile 1.
 

BusaWhipped

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#6
The Busa idles a bit rough. The knocking you hear is stuff (yes that's a technical term)loading/unloading. Turn the idle up a bit more and it'll go away. The slower the idle, the worse it gets. Syncing the throttle bodies will help that too.
 

BA BUSA

MotoGP Wannabe
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#9
Gen1 Busa's...they knock, rattle, and clatter...especially when they are cold.

Just get out there and ride :beerchug:
 

Revolution

revolution custom paint
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#10
i never did the mod, but funny u mention it BA', cause now that i think 'bout it it went away after i switched to synthetic :thumbsup:
 

dadofthree

Seasoned Beef
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#12
I was going to suggest a little higher idle as well. Top end not getting what it needs at lower RPMs. All good thoughts. My Gen II is little noisy up top. I figured it was just the new head they went with. Nothing major, especially compared to some of the other sportbikes I've been on.
 
#13
awesome guys.. making me feel better. I have a small oil pan leak, so def gonna replace the gasket and switch to amsoil full synthetic.. give it a whirl.:beerchug: and up the idle

thanks all!
 

Spudley

Grippin' and Rippin'
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#14
Run the Amsoil.....MCF 10w40 to be exact :oldcool: AND, if the bike "was" drag raced there's a good chance those springs on the hub are probably a little whacked, i.e. compressed. It causes a chatter factor at idle as the idle surges back and forth. No I'm not talking about the clutch springs, I'm talking about the springs behind the fiber/steel stacks that control backlash on the motor from the transmission cluster. It's gear driven and there's a lash effect that most of us won't ever wear out, but then again enough torque can wear them out over time.....This may or may not be your issue but mine knocks a bit while it's warming up. Full operating temp, throttles synched, idle at 1150-1200 she purrs..... :super:

Then again, it might be the cam chain tensioner....check it out !!!!
 

street racer

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#15
The Busa idles a bit rough. The knocking you hear is stuff (yes that's a technical term)loading/unloading. Turn the idle up a bit more and it'll go away. The slower the idle, the worse it gets. Syncing the throttle bodies will help that too.
What BusaWhipped said ! Mine did the same thing when I got it. The idle was at 1,000 RPM. I set it to 1300 and the banging/clanking is gone.
 

BusaWhipped

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#16
If you really want to hear it make noise, put it up on a rear stand, put it in 1st gear and let the clutch out at idle :laugh::laugh: You'll be grabbing for the fast idle lever quicker than the Busa hits 100.
 
#17
I had the same problem, got pretty excited and swapped to amsoil tuesday..... The light knock didn't go away. I brought it to 2 dealerships and they said most run synthetic and one guy had the same thing. Unfortuantly I threw a rod last night. I rode it 2800 miles with the light knock at idle on hot days. And 7 miles on amsoil. Not good. If any one knows a good idea of where to get a motor relativley cheap, that is in good condition please pm me. I lurk alot but i really need help.
 

dadofthree

Seasoned Beef
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#18
The Busa idles a bit rough. The knocking you hear is stuff (yes that's a technical term)loading/unloading. Turn the idle up a bit more and it'll go away. The slower the idle, the worse it gets. Syncing the throttle bodies will help that too.
I was going to suggest uping the idle a tad. When this noise occurs do you watch the idle. It may be dipping for a second or two. There's also a vacuum controlled valve in the airbox that makes a noise kinda like you describe.
 

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