About the Types of Axles in Mountain Bikes

Bicycle axles can be divided into three types: square hole, spline, nail through type axle, and integrated type axle.The specifications of the bicycle axle 

include:

1. Square headed central axis, commonly seen after removing the crankshaft, is a square column with a certain inclination angle.

2. A spline shaft with a groove key on the cylindrical shaft.

3. The through nail type central axis is similar to the traditional flying pigeon, permanent, and phoenix, with a radial flat opening at the end of the cylindrical axis;

4. The crank integrated center shaft is now commonly used in children's strollers. The left and right cranks and the center shaft are integrated, and when installed, 

the crank is threaded through the five way joint from the right side of the vehicle. Based on the commonly used methods and splines, there are three types of five 

way (the part where the center shaft is installed at the bottom of the frame) lengths: 68mm, 73mm, and DH specific long shaft.

Integrated central axis

Just a few years after its launch, various manufacturers have introduced the concept of integrated central shafts and produced them in their high-end series. The 

so-called integrated type refers to separating the axis of the central shaft from the bearing and directly combining it with the crankshaft on one side, while the 

position of the bearing moves from the five way to both sides. The advantage of this system is that it reduces the number of parts, reduces weight, and improves 

structural rigidity. The spacing between bearings is larger, reducing the burden on bearings and improving strength. In fact, this technology has been widely used 

in BMX (small wheeled vehicles) for a lon