skully is right. You have to tighten the cog fully before tightening the lockring fully. Your lockring can be on as much as possible but if the cog can still move then it will unscrew.
@Sumo started
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skully is right. You have to tighten the cog fully before tightening the lockring fully. Your lockring can be on as much as possible but if the cog can still move then it will unscrew.