The engine of a motorbike is made up of different components, and because of the manufacturing process and performance requirements, some components must have a reasonable clearance between them, and valve clearance is one of them.
Valve clearance is strictly speaking a gap between the rocker arm and the top of the valve. The size of this gap varies slightly depending on engine construction and design, but most models are basically around 0.25mm, although the standard value should be based on current vehicle parameters.
When the engine valve clearance exceeds this range, there will be a tada tada ...... sound, as the engine temperature rises this sound will become more and more obvious, if the later use of this sound ignored, although a short period of time will not happen what the situation, but in the long run will certainly have an impact on the gas distribution mechanism, especially the top rod engine, most likely to cause the top rod off.
In fact, the valve clearance does not necessarily get bigger, it also gets smaller, because the valve works as a piston movement, and over time it will sink due to normal wear and tear, and then the clearance between the rocker arm and the valve will get smaller.
After the valve clearance becomes small, there will be a drop in power, starting difficulties and other phenomena, so the later use of the valve clearance needs to be regularly checked and adjusted in accordance with the prescribed parameters, only then the engine performance will play to the best.
As you can see from the above introduction, motorbike engine valve clearance is a normal design clearance, but this clearance will increase with the number of kilometres the engine is used, the wear and tear of the components will deviate, and when it is too large or too small, it will affect the performance of the engine, so the motorbike must pay attention to this clearance in the process of use, or it will cause unnecessary losses.