Just installed a SRAM 8-spd cassette, 11-32, onto an LX hub, the freehub body splines do stop short of going all the way to the outer end, but when on the 11T or 12T rear cogs, there is a noticeable "rumbling", it just isn't smooth. Should I have used a 1mm spacer? If so, in what position do you place the spacer. BTW-the 11T and 12T gears are not attached to the rest of the cluster, if that makes any difference.