Floating discs?
Does it have floating discs? If so it could be the disc moving relative to the carrier. If that is what you can hear, then I wouldn't worry, as long as they're not really badly worn (at the mounting point I mean, not disc thickness).
Lots of people push and pull the forks with brake on and think the head bearings are gone. More often than not it's carriers moving inside the locked discs.
Hope this helps.
Do us all a favour, by bringing yourself up to speed, before pulling onto the motorway.
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