Suspension front fork-the function of spring and air pressure
1.The spring has a long history used in MOTO and it is also the most common type of spring.The hardness of the spring(so-called spring rate )(SpringRate) represents the ratio of force to deformation.Under the principle of not exceeding the load, the pure coil spring has a fixed elasticity coefficient under different stresses and will not be affected by the ambient temperature. After painting or lubrication, the stability and durability are very high. However, the only disadvantage of the wire-side spring is the weight, so the higher-level front forks have begun to use lighter, but more expensive titanium alloy springs.
2.Because the air pressure is light, using air as a spring should be very suitable for bicycles. If you need different hardness, you don't have to replace the spring. You only need to increase or decrease the air pressure. However, the use of gas springs must have more sophisticated technology, high-pressure gas must be completely sealed, once the pressure is lost, it will not work at all. Therefore, the early gas spring had the problem of sealing, and even a sudden loss of all air pressure occurred during use. This kind of problem almost no longer occurred. But just like tires, there is no need to occasionally pump up. The traditional pneumatic front fork also has a so-called stiction problem, that is, the seal (oil seal) that seals the high-pressure air is very tight, and it seems to feel a little stuck. It requires a large external force at the beginning of the compression, so it responds to small amplitude vibration Not very keen. The use of negative springs has basically overcome this problem. The use of gas springs in the mid-stroke shock-absorbing front fork has been quite affirmed, but it cannot replace coil springs on long-stroke front forks.