Can motorcycle valves be adjusted? What's the impact?

The basic structure of the engine consists of 1 cylinder, piston 2, connecting rod 3 and crankshaft 4. Each cylinder has at least two valves, an intake valve and an exhaust valve.

The valve device is an integral part of the engine valve train and plays a very important role in the engine work. The operation of a fuel engine consists of four working processes: intake, compression, work and exhaust. In order to make the engine run continuously, it is necessary to make these four working processes work repeatedly and periodically.

Two of the working processes, intake and exhaust, need to rely on the valve train of the engine to accurately deliver combustible mixture (gasoline engine) or fresh air (diesel engine) according to the working sequence of each cylinder, and discharge the burnt exhaust gas. The other two working processes, compression and work, must isolate the cylinder combustion chamber from the external intake and exhaust channels to prevent gas leakage and ensure the normal operation of the engine. The part responsible for the above work is the valve in the valve train. It is like a human respiratory organ, inhaling and exhaling, and it is indispensable. ?

With the development of technology,

The engine speed is getting higher and higher. The speed of modern automobile engine can generally reach more than 5500 revolutions per minute, and it only takes 0.005 seconds to complete four working processes. The traditional two valves are no longer competent to complete the ventilation work in such a short time, which limits the improvement of engine performance. The only way to solve this problem is to expand the space for gas to enter and exit. In other words, space brings time. Multi-valve technology is the best way to solve this problem. It was not until the popularity of multi-valve technology in the 1980s that the overall quality of the engine made a qualitative leap.

Multi-valve engine refers to a three-valve type with more than two valves per cylinder, namely, two intake valves and one exhaust valve; Four-valve type, with two intake valves and two exhaust valves; Five-valve type with three intake valves and two exhaust valves.

At present, the multi-valve engines in automobiles are mostly four-valve engines. Four-cylinder engine has 16 valves, six-cylinder engine has 24 valves, and eight-cylinder engine has 32 valves. For example, the engine of the Lexus LS400 sedan in Japan is 8 cylinders and 32 valves.

When the number of valves increases, corresponding valve mechanism devices need to be added, which has a complex structure. Generally, two overhead camshafts are used to control the valves arranged on both sides of the center line of the cylinder combustion chamber. The valves are arranged at the inclined positions on both sides of the center of the cylinder combustion chamber, in order to enlarge the diameter of the valve head as much as possible, increase the air flow area, improve the ventilation performance, and form a compact combustion chamber with a spark plug in the center, which is beneficial to the rapid combustion of the mixed gas.