Unchained the roadie and took it outside, first since autumn set in.
Got some kind of hum, like someone slowly tuning a violin. It’s off the front, but there’s no contact on the frame or brakes. In ten years, never experienced the like - it’s weird.
Front wheel has been in the whole time. Admit I haven’t spun it when chained to the trainer.
It’s a Campag scirocco about seven years old.
Off the bike, nothing. Reseated wheel. Nothing. Climbed on and tchaikovsky is getting ready. Get up to speed - nothing.
It’s usually higher pitched than what you describe, but otherwise that sounds kind of like the very very beginning stages of a bearing going dry. Has the hub got cartridge bearings? If so, pop the seals and see if the grease still looks abundant and clean. Salty bearings wouldn’t be a huge surprise if it’s been on the trainer all winter.
I’d remove the wheel from the fork and do a spin while holding the axle in your hands. See if you hear or feel anything in how smooth it is or is not. Per above, it could be a bearing/race/lube issue.
If that is fine and quiet, reinstall in the fork and redo a spin test with the bike in a stand or just by lifting the front end in the air.
Another idea is do deflate and re-inflate the tire and see if it is a bead seating or tube alignment issue in the tire/rim.
If the noise is only present when loaded and rolling, that might point the finger at the tire. Inspect it for casing degradation which can sometimes make sounds that are not present with a fresh tire.
My hubs recently started making a squealing sound, like a very high note from a violin. I thought it was my disc brakes but ended up being the bearings in DT hubs. Tried cleaning and lubing but didn’t remedy a slight friction. Had to order new bearings (tip: purchase bearings from industrial suppliers not bike shops). Once I figured out how to install the bearings everything is smooth riding and best of all quiet.
tchaikovsky is getting ready. Get up to speed - nothing.