How does one messure the heigth in cm of a racing bike??

Question

have a cannondale 3.0 road racing series but don't know size

Answer 1

Cannondale measures size from the center of the bottom bracket (where the cranks attach to the frame) to the top of the top tube (where the seat tube intersects with the top tube, just bellow where the seat post inserts).

Answer 2

Usually the size is measured from the bottom bracket to the top tube along the seat post. Unfortunately not every manufacturer does it the same way. Most commonly, measure from the center of the BB to the center of the top tube (c-c). If the bike has a sloping top tube you would measure to where the top tube would be if it wasn't sloped (virtual top tube). The virtual top tube would be parallel to the ground when the bike is standing upright.

Answer 3

call 1-800-bike-usa and give them the serial number (on teh bottom side of the bottom bracket. On an older 'dale, you may need to peel back the plastic cable router to get the complete number. they can tell you the year of manufacture, and the size.

Answer 4

Measure from the middle of the bottom bracket to the top of the seat tube.  That distance is the size of the frame.