I need to install a 7-speed cassette on a Hyperglide freehub. This cassette is narrower than the freehub's spline height (meant to accommodate 9 and 10-speed cassettes). I also bought an additional spacer which was supposed to take up the slack:
When the parts had arrived, I discovered that the freehub's body was designed for 11-speed road Hyperglide. That is, it was even longer. The spacer that I had already bought was not enough to compensate for the height difference.
So, I need to use a second spacer to convert it full way from 11 speed road → 10 speed MTB → 7 speed, and then finally fit my cassette.
I have a lot of spare plastic BB spacers meant to be used with 68mm bottom brackets shells to accommodate 73 mm BBs.
Such a spacer fits on the freehub body. Its height is close enough to what I could have if I used an "official" spacer. It does not have splines to prevent it from rotating.
Would this arrangement (two plastic spacers) reliably work? To clarify, I am offsetting the whole cassette, not individual cogs on it.