Are my wheel bearings knackered? (video)

[elbrownos]

So I thought I'd knackered my chain (see this thread http://foc-u.co.uk/index.php/topic,9648.0.html )
But I was advised to pop the chain off and see if it was the chain or the wheel bearings.
I've posted two videos - one with the chain off and one with the chain on.

Chain off:
Wheel spinning - no chain
I'm guessing it's not supposed to make that knocking noise?

Chain on:
Wheel spinning - with chain
It doesn't spin nearly as long as it did a few weeks ago, which makes me suspect the chain.
And the chain does sound really noisy. But I had a good feel of it and there were no tight links. I'm not sure what a new chain feels like so I can't tell if the whole chain is stiffer than it should be.
Also in this video you can hear a high pitched squeal from the wheel when it's turning slowly.
The bike's still riding fine and the weird noises at the rear have almost gone away.

Any thoughts appreciated.

[Dead Eye]

Its definitely catching at the same point on every revolution - have you checked the disc to see if its catching on the pads. Same test but with the caliper removed would identify it - hard to hear where exactly the noise is coming from in the video.

If its definitely on the left, how does the sprocket look in terms of alignment?

[AdieR]

On your top video (chain off), your sprocket looks like it's "wandering" from side to side to me, almost as if it's warped - how long have them chain / sprockets been on the bike? Have you had any work done recently eg new tyre / brakes?

Check your wheel alignment / sprocket alignment, and a check of your cush drive rubbers is probably in order too.

[stevierst]

The sprocket carrier bearing could be knackered, mine went, and I only noticed when I took the wheel off to change the tyre. I spun the wheel without the chain on, and my sprocket was a bit 'wobbly', but the wheel was true. Might be worth a look.

[elbrownos]

Thanks guys
I'm certain it's not related to the brake.
Sprocket is perfectly straight as far as I can tell.
I'm puzzled about why the knocking is only there when the chain is off.
What are the usual signs of worn bearings? I can't detect any play moving the wheel side to side.
I'm due for a new rear tyre soonish so I think I'll wait til the wheel's off and check everything out properly.