I have a 2009 Motobecane 18 speed road bike. I have been riding for a few months now and now I’m looking into adding more gears to her. The question I have is, is it as simple as changing out the rear 9 gear set to a 10 or 11 gear set? I realize there would need to be some adjustments afterwards but would there need to be any other changes done to the bike.. Thanks for all your advice..