The position of the rocker pivot is the same on a M900Sie and an S#R frame.
So if you transplant the whole Rocker, link and arm assy as one, from an S2R or S4R it should all work okay...Provided that the relavant widths are the same or shimable.?
PM me your email. I will send you 3 PDFs with loads of info on S4R suspension, frame and rear wheel.
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