Originally Posted by
dddd
They tout those as freewheel spacers, but using aluminum for a freewheel spacer too often results in a very uneven seating of the freewheel body on the hubshell as the soft spacers tend to squeeze out asymmetrically or eccentrically from between the hub and freewheel. A wobbling freewheel is then the result.
I've even seen the alloy spacers split and move out of place when securely tightened under a fixed cup flange, and I've also seen where someone used a plastic spacer under the fixed cup.
Steel is real.
Not sure if the spacers on the green SC above are steel or aluminum (I seem to remember that they are zinc plated steel) but I've done over 2500 miles on the set-up with no issues, fingers crossed. Its the first bike I ever built. So far so good. I have one on the freewheel too, to keep the derailleur from ticking the spokes.