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So I am upgrading my Trek 1.1 (2016) from 8speed Shimano Claris to an assortment of Shimano Ultegra 6800, 105 5800. I just bought a 11speed cassette to complete the major parts (it hasn't shipped yet). Will I also have to buy a larger free hub assembly so that the new cassette will fit? I've never measured the difference so I'm not sure if its necessary.