Can one use m8000 replacement sprockets 11T 13T 15T to replace the corresponding mx80 sprockets?

I appreciate the clusters can't be switched due 3 free sprockets and 2 clusters of 4 on mx80 vs 5 free and 2 clusters of 3 in the m8000, but what about the first 3 sprockets?

mx80 https://factoryjackson.com/2017/04/19/sunrace-mx80-11-50-11-speed-cassette/

m8000 cogs https://www.hibike.com/shimano-cs-m8000-11-speed-sprocket-11-pa913bedaac0e23a55c569d6d78f42bc7


While this is not a definitive answer it may help with your decision. If you look closely at the mx80 you can see that some of the teeth on the larger cogs have some extra machine work (notches) done. These areas are to facilitate the chain moving from one cog to the other. For optimum performance the "notches" must be correctly aligned. The variation in the width of the splines on the freehub make this alignment foolproof. Looking at two 9 speed cassettes in my parts bin, the indexing of the notches on the cog and its position on the freehub is not universal between all brands. What this means is that while the cogs may fit, shifting performance may not be optimized.

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    Correct - it might take an extra half-revolution of the cassette before the ramp catches up and assists the chain up. – Criggie Dec 30 '17 at 0:25
  • I'm happy to accept this as a correct answer, my main concern was that I was overlooking something in my assumption that they should work, and this answer shows me something I did overlook. I doubt anyone has actually tried this, as relatively few people buy replacement sprockets and fewer still have this cassette, so I doubt anyone will come along with a definitive answer. I'm going to buy the mx80 anyway for the bit of extra range and deal with the issue of me knackering the 15T sprocket when I come to it, I'll try to report back on alignment when the time comes. – Purr Dec 30 '17 at 2:40

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