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

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • 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 ]

Related Content


Michigan Motocross Tires by 288yz450

Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply

100 hrs on 2014 yz450f, shim valves or replace them? by ttr230rider6

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  79 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

Yamaha YZ450F 2017 by Chris.GVS

Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.