I bought a new bike (Cannondale Synapse) recently and I can't adjust my front derailleur in enough. It bottoms out against the frame and the chain rubs in some gears. I didn't like how the LBS that I bought it from put it together, so I took it to a shop recommended by members of my club. The mechanic at the recommended shop told me to have the bottom bracket replaced with a wider one to allow more adjustment. Does this sound right? If so, should I ask the shop where I bought the bike to replace it since the original didn't work?