So I was lubricating my chain, and I happened to notice the 11 tooth cog had a significant wobble.
The gear would of yen catch the chain when back peddling the bike. So, a bit of investigation was in order. Taking the cassette off the freehub, it was obvious there was a lot of ring bite into the freehub splines. This is where the force of peddling the bike causes the mounting lugs on the cassette to wear a grove into the freehub splines. Not a massive issue on the middle cogs where it often occurs.
However, the 11 tooth kinda sits off the hub, and looking, there was some big gouging on the splines causing the cog to sit angled. So I tried filing off the worst parts. But this didn’t help, causing the lock ring to be angled on the cog.
So, the only option is to replace the whole freehub, and luckily I had a spare wheel available. So a quick change over, and ensuring the lock ring was REALLY tight, which should go some way to completely clamp the cogs down, keeping any movement to a minimum, hopefully should be the end to cassette wear.
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