Hmm, only things I can think of: Wheel itself. Is it bolted on properly? (May sound obvious, but I've seen more than one car have a wheel fall off! Not mine I might add). CV joint. If the inner or outer CV joints are about to fall apart they might be knocking. Is the sound worse when turning sharply?
Try jacking the wheel up and turning it by hand, see if you can find where the sound's coming from.
If it were the bearing, I'd expect a low droning noise incresing with roadspeed, not a knocking. (though a ball-joint like clunk can be heard sometimes too).
Doubt the brakes would have anything to do with it, unless you've got a cracked brake disk - but I doubt that a lot.
I tend to think because it disappears when you're freewheeling it's going to be driveshaft related.
Try jacking the wheel up and turning it by hand, see if you can find where the sound's coming from.
If it were the bearing, I'd expect a low droning noise incresing with roadspeed, not a knocking. (though a ball-joint like clunk can be heard sometimes too).
Doubt the brakes would have anything to do with it, unless you've got a cracked brake disk - but I doubt that a lot.
I tend to think because it disappears when you're freewheeling it's going to be driveshaft related.