• The two notches you reefer to are for dissembling the actual freehub, rather than freehub removal. The tool for this is no longer made, you can bodge a tool togethet or use a punch to do this but as stated, this is only for complete dissemble of the free hub, you will end up with ball bearings all over the floor and be able to play with the springs and paws. It's largely a pointless task as shimano spare parts are not available and freehub failures tend to involve damaged paws or springs, if you have a damage freehub replace the entire freehub body and for that it's the 10 mm allen key job I talked about in the previous post.

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