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Knock on a CBR250RR at idle

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by MattyB, Jul 30, 2006.

  1. hey people... i'm not sure if it's anything to be stressing about, but when cold, on idle, my CBR sounds (too an ex car mechanics ear) to be pinging/knocking a tad :\
    just a soft metallic knocking in rythm to the rpm.

    doesn't get any louder or faster when i rev it, i'm guessing because the exhaust drones over it, or it evens out.

    and i'm 60% sure it goes away when it's hot (will check today after a ride).

    the fuel in it was put in by loz, and he concured he used the right fuel with the mechanic when they were randomly talking about it.
    so, i doubt it's the fuel.

    might be nothing, might be something..
  2. My babyblade had the same issue. Happened to be a problem with a cam
  3. probably cam chain rattle
  4. hrm, big fix?
  5. recently found out that cbr250's dont run a cam chain, instead the cams are driven by gears. so i dont think it is this.

    Maybe get a valve lash done to see how its running and if there is anything you need to worry about.
  6. Yeah cbr's use gears not chains on the cam.
    The noise could be the lifters which may need adjusting.