whistley chirpy kind of noise?

9 replies to this topic
  • st400f

Posted February 04, 2002 - 10:00 PM


lately i have noticed that i have this whistley chirpy kind of noice it seems to be from the engine right side any ideas?

  • Shawbridge Husky

Posted February 04, 2002 - 10:28 PM


I had similar symptoms before replacing lower crank bearing. What year bike and how many hours on your engine?

  • Shawn_Mc

Posted February 04, 2002 - 12:03 PM


A quick check, pull the clutch cover make sure the inner hub hasnt gone away. Sometimes the steel insert in the casting comes loose. Mine did.

  • thumpsalad

Posted February 04, 2002 - 01:08 PM


I get this noise, too after the clutch has some abuse from a ride. It is most noticeable when I take off from a stop and hammer the clutch hard sometimes. I also notice it when I lug the motor at slow speeds.

Oil has been good and no discoloration or metal particles in the filter or strainer. I change it after 2 rides or 10 hours. Motul 3000 4-stroke oil.

I think I will be inspecting my clutch components this week!

  • mcarp

Posted February 08, 2002 - 11:01 AM


other stuff to check

-loose bolt with galled metal
-lean jetting
-wheel bearing

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  • thumpsalad

Posted March 03, 2002 - 06:47 PM


I thought I would revive this post since there were no real definitive answers so far.

Anybody have any clue? I pulled both side covers and everything looks good. Clutch is in good shape. My bike is a '99.

Now, last night I did find some very small metal particles in the filter during my routine maintenance. I change oil every 3 rides. Any help is appreciated!

  • Smiley_104

Posted March 03, 2002 - 10:19 PM


I get the chirpy sound also. Mine comes from the airbox when I give it gas. However I ride the CRF, but you might want to check and see if the noise is coming from there. Just a thought.

  • sirthumpalot

Posted March 04, 2002 - 03:03 AM


I get this noise too (from the carb/airbox) when not giving it a lot of gas. It must be the air going by the carb slide. Do you get the noise when you're on it hard, or only when you're giving it about 1/2 or less throttle?

  • thumpsalad

Posted March 04, 2002 - 06:06 AM


When I first got the bike used), it didn't make the noise. Now, after having it for 3 months, it makes that strange noise. It's more of an oscillating whistle or chirp noise instead of a smooth single pitch whistle and it's only under heavy acceleration...not when I am already moving at a constant speed. I even pulled my wheel-bearings just to be sure and they were fine.

I don't know how else to describe it!

  • Dodger

Posted March 04, 2002 - 04:00 PM


Mine does it also. Someone asked basically the same questions on the WR side. Most people thought it was a common sound for these motors, they actually called it the "Tweety Bird" :) ! Concensus was that it was no big deal...........

Hope so :D !

Dodger :D :D

[ March 04, 2002: Message edited by: Dodger ]

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