Originally Posted by alcjphil

What specific bike are you asking about? What wheel upgrade are you thinking about? Carbon wheels for bikes with rim brakes are a 2 way street. You trade poorer braking for a tiny weight reduction, and maybe better looks at who knows what cost. With Disc brakes things change. You get better braking under all conditions. Yes, disc brake bikes are a tiny bit heavier, but they are better. Knowing what bike you are asking about would allow people to give better advice.