Transmission sprocket nut for rigid XLs should all be the same wrench size: 1-7/8“ (47.625mm) .
It's a 6 point nut and will require a 6 point socket to remove / install.
Normally, the sprocket holding tool below is used to keep the sprocket from turning while removing the nut.

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Final drive locking tool from J&Pcycles.com part # (910-576).
Don't forget to buy a longer grade 8 bolt to use as a stop for the tool.
Just pick the hole your going to use and but one from an auto parts or hardware store.

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DIY by Graywolf of the XLForum - See thread here: https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-general-discussion-and-problems/168260-final-drive-pulley-tool-12-50-usd?t=1806002

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