The right-hand rifle as part of a race bike with two mounted sprockets (front blades).
A crank, or in the Dutch crank, is the connecting piece between the pedal of the bicycle and the pedal. The cranks and the two or three sprocket wheels (front blades) together form the crankset. These sprocket wheels are removable so that the gearbox can easily be changed. In turn, the crankshaft and the crankshaft (including the pedals and bicycle chain) together form the bicycle drive system.
In addition to the chain wheels, the length of the crank can also be adjusted to the inner leg length of the driver of the bike. This crank length is usually 20 to 21 percent of the leg length.
The design of the cranks determines the Q-value, the distance in millimeters between the outer sides of the cranks, with a smaller number of biomechanical, aerodynamic and mechanical advantages. In addition, the shape of the crankset can affect the chain line.
The crank shaft can be mounted on the trapas in five different ways: via the JIS system, the Spie system, the Octalink system, the ISIS system and the Hollowtech II system.
In the Netherlands, spikes were used in the past - only the more expensive race bikes had crazy cranks. Nowadays almost all bicycles have idle cranks.
One-piece cranks were common in the somewhat older American bikes, especially with low-cost bikes and children's bicycles. The two cranks and the trapas form a whole. The bracket and air are designed in such a way that the cranks can be easily swapped if necessary. Note
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