However, according to the rules of any model bike is manufactured in several necessarily Rostovka-size. And the size is determined by the size of the bicycle frame. And more specifically - the distance from the axis of rotation of the pedals to the horizontal line passing through the upper end of the seat tube. The size of the bike can be found at this very pipe, expressed alphabetic characters or digits in inches or centimeters.
For example, the average size of the bicycle can be indicated: or M - Medium, or 18 "or 45, 7cm.
Due to the fact that the geometry of the frame from different manufacturers and different models, the true dimensions of one marking bikes may vary. However, these differences are insignificant.
In the end, you can always spend extra debugging bike under your height and leg length, raise or lower the seat, take him a little back or pulling forward. Its most comfortable position on the bike can also be derived Steering wheel height and tilt.
In practice, if you get a bike for yourself, do the following. Be close to your favorite model, perekin'te foot through the frame and look around. Between the crotch and the frame you should remain in 7-10sm space, which is about the width of the palm.
This requirement will allow you to stand freely, without leaving the bike and hit with a sharp stops unexpectedly.