Motorcycle shock absorbers can be divided into two major categories: single-cylinder shock absorbers and double-cylinder shock absorbers. A double-cylinder motorcycle shock absorber refers to a shock absorber with two cylinders, an inner and an outer one. The piston moves in the inner cylinder. Due to the entry and withdrawal of the piston rod, the volume of the oil in the inner cylinder increases and contracts accordingly. Therefore, it is necessary to maintain the balance of the oil in the inner cylinder by exchanging with the outer cylinder.

Therefore, there should be four valves in the shock absorber of a double-tube motorcycle. Besides the two throttle valves on the piston mentioned above, there are also the flow valve and the compensating valve installed between the inner and outer cylinders to complete the exchange function. Compared with the double-tube type, the single-tube shock absorber has a simpler structure and reduces a set of valve systems.

It is equipped with a floating piston at the lower part of the cylinder barrel. Below the floating piston, a closed gas chamber is formed and filled with high-pressure nitrogen. The changes in the liquid level height caused by the inflow and outflow of oil by the piston rod mentioned above are automatically adapted to by the floating of the floating piston.

In addition to the two types of motorcycle shock absorbers mentioned above, there are also adjustable resistance shock absorbers. It can change the size of the throttle hole through external operations. Automobiles adopt electronic control shock absorbers as standard equipment. They detect the driving status through sensors and calculate the appropriate damping force by computers, enabling the damping force adjustment mechanism on the shock absorbers to operate automatically.

After confirming that the shock absorber of the motorcycle is faulty or has failed, it is necessary to first check whether the shock absorber is leaking oil or has any traces of old oil leakage. It might be that the oil seal or the sealing gasket is damaged or failed. New sealing parts should be replaced. If the oil leakage still cannot be eliminated, pull out the shock absorber. If you feel it is stuck or the weight is uneven, further check whether the gap between the piston and the cylinder is too large, whether the shock absorber piston connecting rod is bent, and whether there are scratches or pull marks on the surface of the piston connecting rod and the cylinder.

If there is no oil leakage from the motorcycle shock absorber, it is necessary to check whether the shock absorber connecting pins, connecting rods, connecting holes, rubber bushings, etc. are damaged, de-welded, cracked or fallen off. If the above checks are normal, the shock absorber should be further disassembled to check whether the fit clearance between the piston and the cylinder is too large, whether the cylinder is scratched, whether the valve seal is good, whether the valve disc and the valve seat are tightly attached, and whether the extension spring of the shock absorber is too soft or broken. Repair should be carried out by grinding or replacing parts according to the situation.