Just started riding my tarmac elite and I'm still getting a feel for it. The question is: In order to change from the large ring to the small (or vice versa) in front, is it necessary to be on the biggest or smallest in the back first? Or can you switch the front ring whenever you need to? I seem to be having trouble, sometimes the front derailleur doesnt do anything when i try to change it. (if it helps, i have SRAM Apex shifters)