Yeh have been in touch with Micheal in Greece and he is fairly sure the R5/6 cranks bearings are the same as the MC21 but not 100%

Have done many searches actually, and this particular issue seems untouched unless I missed something

Be good to know exactly what the differences are between the R5/6 MC18 crank and the MC21
Below is the right side outer bearing off the R5 and the crank without the outer bearings
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