Road Cycling - how should it fit?

I've noticed that everyone emphasizes fit, fit, fit. Just out of curiosity, how do I KNOW the bike fits? Right now, I feel like if I get down into a more aerodynamic position, I am getting a lot of pressure from the seat. Does this mean the bike is wrong, or does the seat need to be tilted differently or what? I'm 5'9" with a 54" frame, so I wouldn't think I"m reaching too much.

The seat itsself could be wrong,the tilt may be wrong the bars may be too low the stem could be too long you might meed more saddle time.Lots of possibilities and the frame could be the right size and still be a torture chamber because of all the other variables. Something one has to sort out.Often a good fitter at LBS can evaluate your position on bike and make recommmendations.

wrenchscience.com has the best fit kit I have found thus far. Go through that process, and see if it help at all.

Do yourself a major favor and find a bike shop that can do a fitting. There are bike fit kits that some shops have that can measure acurately top tube lenght, seat tube, stem, rise of stem etc.. You then can purchase what you need. It is probably the most important thing you can do.

I second the statement above: the frame may be OK but the components may not.

I just did an experiment with stem length. I felt like I was stretching out too far, even though the axel disappeared when I looked down through the handlebar the way it's supposed to.

I was riding a 100mm low rise stem. I ordered an 80mm stem with a slightly higher rise. I put the new stem on yesterday and rode around my normal 10 mile loop.

Man, I couldn't wait to get home and put the 100mm stem back on. The 80mm was torture. My insides felt all scrunched up. I couldn't breath as easily. My balance felt off and the steering was twichier.

I'm back to being stretched out. The bars could stand to be a bit higher, but maybe not. Probably the bike shop fitting is a good idea.

condor

There are 2 ways of getting aerodynamic.

The traditional time-trialists method is to lower the bars. This will make your hip-angle smaller and probably put more pressure on the front of your saddle.

The triathaletes method is to pivot the whole body forward about the bottom bracket. The saddle comes forward and up, the bars come forward and down. This maintains a relaxed hip angle but puts more weight on the arms, which are resting on aerobars.

You should use the output of any fitting system as a guide only, but be guided mainly by your own sense of comfort and efficiency. It can take a long while to perfect a position, and to get used to riding in a more extreme aerodynamic position. Some aero-positions are strictly for competition use, you wouldnt want to train or ride all day in them. Are you looking for a comfortable , efficient riding position or a race-winning one?