On Sunday, November 10, 2013 8:52:53 AM UTC-5, wrote:
I have these Mavic Equipe 2009 wheels, very solid wheels lots of miles. They are making a buzzing sound after hitting a bump over 20 mph. The buzzing goes on until

I slow down. I did find play (in the bearing) with the wheel installed. I tightened the bearing, but the issue came back. I had a local bike shop replace the bearings and the vibrating bearing are back again with the new bearings. The headset is tight, no play and brakes are normal.

Anybody have any ideas?

Is was the free hub making the sound. It was louder when pedaling backwards, so I knew right away that I was wrong. But now know for sure what it is.
I took the cassette and freehub off and found out the the bolt and nut holding the freehub on was loose (could turn by hand). Cleaned everything, lubed with mineral oil and reassembled. Have not ridden the bike yet, will ride today.