Have recently treated myself to a new road bike, and have a wee bit of a problem - I am much slower on my road bike than on my (bigger and heavier) hybrid. Hills that I can climb easily in 52x22 on my hybrid are giving me trouble even in 39x24 on my road bike. I also seem to have a lot less stamina and power on my road bike, and the muscles in my legs start aching much more quickly. Is this just because I have to get used to the different riding position, or is it an indication that my saddle/seatpost/bar are not set up right?