Sounds suspiciously like the rim tape has worn and the top of a spoke is rubbing on the tube.
Happened to me once, I wasn't amusing, although I wasn't on a trainer at the time!
@Sam started
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Sounds suspiciously like the rim tape has worn and the top of a spoke is rubbing on the tube.
Happened to me once, I wasn't amusing, although I wasn't on a trainer at the time!