Noticed this odd clunk? Sound in the forks yesterday. I checked and nothing is hitting anywhere. Threw the front tire on the stand and the bearings seem fine.
Try sitting on the bike and holding the front brake. Push up and down on the handlebars and see if the fork action is smooth and relatively quiet.
If you can't easily replicate the clunk sound, I wouldn't worry about it until you hear it again. If we worried about every odd noise coming from our bikes, we would never ride!
I tossed Superzoom a thanks because it's true. We simply can't worry about every little noise or we'll go mad.
In my experience riding bikes though, I've never heard a clunk like that in my forks and I've been riding since the mid-eighties.
If you're sure nothing is simply bumping against another thing, I'd suck it up and take it somewhere to have it checked out. I've rebuilt forks because they were leaking, but I've never heard one "clunk."
First though, I'd be sure it was the fork that was making the sound, and not something else that "clunked" when the fork was depressed.
I'm pretty sure it's coming from the forks. If I sit on the bike they move smooth but I do feel a slight bit of vibration when I hear the sound. I ran her for just over 200 miles yesterday though and she rode like a champ like usual, didn't hear or feel anything while riding.