http://www.xt660.com/showthread.php?t=21930

Hi mate, had the same problem.

The solution is not in the rubbers or packing them with inner tube (although you should do this)

Replace the bearing inside, and get a chain alignment tool to ensure this doesn't continue.

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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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