For me, cycling is not so one dimensional as either the bike or the rider. I understand that it is the riders fitness, attitude and ability that will dictate the ultimate speed and distance covered, and I train hard to achieve that. But I also love the bicycle itself as a work of machine art and mechanical wonder, so as a parallel benefit I get fitter, stronger and also get an object to look at, tinker with and enjoy.
So for me it is both the bike and the rider, for different reasons