What size bike frame?
Go to your local bike shop. Make lots of bike buying noises. Get them to recommend bike sizes. Problem solved. Sizing your bike is relatively easy. Firstly, stand over the frame. You want between 2 and 4 inches between your family jewels and the horizontal bar, so that if you dismount you are not going to feel it. Next, lean against a wall, while sitting on your bike. Put your heal on the peddle and rotate the crank to the lowest part of rotation. When your leg locks out, you are at the right length. (I.E. your leg will be slightly bent when riding on the balls of your feet.). This is the corect set up for your bike. Long seat posts, providing that it does not go over the safe max extension is good. It flexes as you go over bumps and therefore acts like suspension.
