Yeah, I've had the inner tube in there since I changed them about 7,000 miles ago.
And I know the rubbers disintegrate, not worried about them.. they're �20

But it's that dry metal dust that worries me.

You can see in the pic with the red arrow, that there's scuffing all around that hub and its receiving hole in the sprocket carrier.

These two surfaces are clearly rubbing together. It's not rubber crap like in the spaces for the cush rubbers. It's definitely a metallic dust.

That's going to be a pig to clean, as I hope it doesn't enter the bearing.
First thing tomorrow, I'll have a crack at that.

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Bike: 2013 XT660Z, TKC70 tyres

Mods:
Barkbusters, Scottoiler, DIY Tail Mod, DNA Stage 3, Power Commander V & O2 Eliminator, Exan X-Black Stainless exhaust, Tool tube, Ohlins linear front fork springs, Nitron rear shock, JT front and Supersprox rear sprockets, D.I.D. VX 520 chain, Adventure Spec bashplate, DIY USB Outlet, DIY chain guide, Kev's Throttle mod

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