The correct fit for a flat 20inch bmx bike would be a rider that stands 155 cm.
Bmx bike sizes.
Most bmx bikes have 20 tires while the larger frames may use 24 tires also known as cruiser class bmx bikes.
Height ft in cm top tube in crank size mm 4 122.
As a minimum you will need at least a 23 inside leg to be able to stand over a full size bmx bike.
Bmx bike frame sizing is generally measured in inches in.
Bmx bikes come in a bunch of different sizes ranging from 12 all the way to 26.
When figuring out frame size only the rider s height is important.
Including 20 25 20 5 20 75 and 21.