How to Determine the Correct Frame Size for a Bike


How to Determine the Correct Frame Size for
a Bike. When purchasing a new bicycle, be sure to
take measurements and get the right fit. Just a push — and a few numbers — and you’re
on the way! You will need Wall Book Measuring tape Calculator
Body type knowledge and test rides. Step 1. Measure your inseam by standing barefoot with
your back against a wall, looking straight ahead. Hold an inch-thick book between your legs. Measure the distance in centimeters from the
top edge of the book to the floor. Perform the measurement three or four times
and calculate the average. Step 2. Determine your measurement for a center-to-center
measured road bike frame, which measures from the center of the bottom bracket to the center
of the top tube, by multiplying your inseam by .65. Step 3. Figure your measurement for a center-to-top
measured road bike frame, which measures from the center of the bottom bracket to the top
of the top tube or seat lug, by multiplying your inseam by .67. This accounts for the additional length of
the top of the seat tube. Step 4. Adjust your measurement by subtracting 10
to 12 centimeters from your center-to-top road bike size and converting it to inches
to determine your center-to-top mountain bike size. Convert centimeters to inches by multiplying
by .3937. Step 5. Since women generally have longer legs and
shorter torsos than men, women should look for frames with shorter top tubes or frames
that are specially made for women. Men with shorter upper bodies or who prefer
a more upright position should also consider frames with shorter top tubes. Step 6. Divide your height by your inseam if you have
unusually long or short limbs. If the quotient is more than 2.2, you will
need a longer reach or top tube. If it is less than 2.2, you will need a shorter
reach or top tube. Step 7. Test ride several different frame sizes, taking
into account any top tube length added by the saddle post, to get a clearer idea of
the size most comfortable for you. Did you know Of the 60 riders participating
in the first Tour de France in 1903, only 21 finished the race.