Motorcycle engine as a complex mechanical system, in order to ensure convenient maintenance, do safe disassembly and assembly, many assembly parts are set up a positioning pin or limit clamp spring.

It's so small that a lot of people ignore it, but in fact, as an integral part of a complex system, every little thing has been shaped by thousands of trials, and it's necessary for its existence.

Some repairmen said that these small parts are not installed, do not affect the car driving. Is this really the case?

※※ What happens if the locating pin is missing?

If the cylinder positioning pin leaks, it will cause cylinder, plug and ring partial wear, resulting in the engine power output decline, driving weakness, can not afford to run at high speed, greatly increased fuel consumption, more serious wear, will also lead to cylinder pad dislocation, resulting in oil leakage.

If the positioning pin of the gearbox is missing, it will cause the combination of the box body to be not in place, the main and auxiliary shafts to be misplaced, reducing the contact area of the gear, leading to the oil leakage of the box body, the wear of the gear is aggravated, and then more serious, it will cause the gear to hit the teeth.

If the crankcase positioning pin is missing, it will cause the crankshaft power output stuck, difficult operation, affecting the engine power performance.

If the positioning pin between the multi-cylinder engine and the gearbox is missing, it will cause the starting motor to beat teeth.

※※ What happens if the locating pin is incorrectly installed?

If the positioning pin is installed too long, it will affect the sealing performance of the relevant parts of the engine, resulting in oil leakage of the crankcase and gearbox, cylinder head and the gasket between the cylinders burning out, the engine starts difficult and the driving is weak.

If the positioning pin of the cylinder head is too long, it will lead to the loosening of the CAM operation, large noise and weak engine.

If the positioning pin is too thin and too small, it will lose the positioning effect, resulting in various faults of the missing positioning pin, resulting in the fixing screw can not be tightened.

If the positioning pin of the oil passage is misinstalled or too thick, it will block the oil passage, affect the lubrication effect, cause abnormal wear and tear of the engine, and affect the engine life and power output.

In addition, the positioning pin has its own specifications, replacement needs to be strictly in accordance with the relevant standards, not free to replace the material, or Zhang Guanli wear!