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I'm considering upgrading from a 9-speed, 12-26 cassette on a 2006 Lemond Alpe D'Huez. I have a triple front chairing with a Shimano 105 groupset, with one exception - an Ultegra rear derailleur. Can I do this by changing both derailleurs, the chain, the cassette, and the hub on my existing rear wheel? I have a lot of hills in my area, which is why I'm looking into possibly a 10 speed, 12-30. Thanks for the help!