Ok, I seen topics on the "mysterious noise" occurring on 2001 WR426's. I thought like many it was either chain slap or kickstand issues. After only the 3rd ride on my 2001 WR. I have discovered that magnets on the magneto have come loose/off & have permanently damaged the stator. I am in the middle of the Yamaha Political mess to see if they will cover the expense to repair/replace. I have had this bike since Dec 2000, but rarely ride it due to my Motocross schedules on a YZF426. I am hoping that because of my purchase of 6 Yamaha's in 3yrs, that they will respond. For those interested: check for any binding in the stroke on the kick starter, even if it is only one kick out of 20. Also, if that noise always seems to be different,or seems to change, check under both your ignition & clutch covers for any sign of damage. I unfortunately do not know a lot about motorcycle electronics, so I hope the description in this post came out clear. Has anyone seen this before???