The right fit is more about top tube length than anything else. Just about everything else can be greatly adjusted. Every bike has a different bottom bracket height and every cleat has a different stack heigh. This means that judging your saddle height by where your feet touch the ground will not be consistent from one bike or pedal to another. I have very long arms and prefer a 19'' mountain bike at 5'9''. When I am on the seat, it's perfect, but I touch when over the top tube because the bike has a tall BB height. If you don't have a tool to measure a knee angle of about 30 degrees when your leg is fully extended, a good close indicator is to just be able to touch the pedal with your heels at the bottom if the pedal stroke.

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