[henryj]

I have not yet set up my new spindle, also a 2.2KW/24K RPM but a different manufacturer. For breaking in the bearings they recommend raising the speed in increments of approximately 3000 RPM, and letting it run 20 minutes before the next 3000 RPM increase. It ends up being about an hour for each increase of 10K RPM. So for ours about 2.5 hours break in time.

Thanks. I wish the manufacturers would put colorful stickers to that effect on new spindles. Don't know how a new user should be expected to know. My old Porter Cable 7518 router mentioned in original post ran from the get go at 21,000 RPM, never required break in, and it's bearings have been going strong for some 12 years now. So I didn't expect this.

Has anyone else been able to listen to the noise in the .zip file? mactec54 has been very helpful, but I'd appreciate a second opinion from another spindle owner. While I think it's bearings, I could still be wrong on that.