I have purchased a set of Shimano WH-R550 wheels on ebay for $70 and I am going to use them as back up, I have a 9 speed set up on the bike now and am going to put a 9 speed cassette on the new wheel, Questions is do I need a spacer or anything out of the ordinary I should be aware of, Shimano says the hub is 8 9 or 10 speed compatible. Thanks for any help!!!
