I got a used 12-27 Ultegra cassette to go on my budget/commuter bike. It came with all of the in-between spacers, but not the low 1.0mm spacer pictured in here: http://techdocs.shimano.com/media/te...9830608752.pdf
Do I need it with the particular wheel I am using? The wheel PDF doesn't mention it. The 8 speed HG50 I took off didn't have a spacer.