Tag Archives: friction

Analysis of clutch failure

Here is some analysis on failure models in the process of using the clutch.

Skid
Clutch can affect a smooth start, transfer power and shift smoothly for the motorcycle and it is an important part to make the motorcycle safe, practical and comfortable.

There are many different reasons for this phenomenon:

1. Different material of the clutch friction plate. The wear-resisting performance for those high quality clutch kits are much better than those common clutch under the test of same load and usage time. Of course, the price of high quality clutch is also much higher than the common one. The motorcycle rider can choose high quality or common one according to their needs.

2. Motorcycle overloading will cause abnormal wear of the clutch. With the serious wear, the clutch will suffer skid soon, so it is better for the rider not to overload your lovely motorcycle.

3. Improper maintenance of engine.
3.1 The engine oil has not be changed for a long period, then the oil will have high viscosity and there will be iron scrap inside, which is the main reason for the wear and tear on the surface of clutch friction plate.
3.2 When the clutch control is loose, and the users don’t adjust it in time, then the clutch will be always in the half clutch for a long time, which is a dangerous running condition.

Abnormal noise
Change of load or the moment of clutch engagement during the period of driving the motorcycle may cause abnormal noise.

There are several reasons:

1. The uneven abrasion between friction plate and steel plate will cause sharp sound at the moment of clutch engagement.

2. The contact surface of center bush and pressure plate is too dry because there is no oil on due to the oil viscosity, and then the friction plate will do dry friction and produce abnormal sound.

3. Locking mechanism or adjusting mechanism is loose in the process of using will cause the clutch lose dynamic balance. After a long period of usage, there will be abnormal sound between the parts.

The above three factors which cause clutch noise can be solved by daily maintenance, replacement or adjustment.

In addition to the above three reasons, if the flatness of friction plate is terribly bad or the thickness is uneven, then these will also cause abnormal noise. This requires clutch manufacturers be in strict accordance with the standard and control the height difference and flatness, in order to reduce clutch noise.

Friction plate burnout
The friction material fall off from the friction plate, that is friction plate burnout.

The main reasons are as follows:

1. the friction material doesn’t bond firmly. Main phenomenon is that some friction material is left on the plate after burnout. This kind of situation is very rare, because friction plate manufacturer will do an overall test about the adhesive force before they leave the factory.

2. The friction plate can’t carry too much load and then cause the friction burnout. In this situation, the friction material will fall off, charring on the surface and have a burning smell. This kind of phenomenon is caused by many factors, such as overload, poor quality of engine oil, poor friction materials and incorrect clutch operating mode, such as climbing with half clutch or speed up and gear shift when going up the slope.

Plate burnout have a large influence on driving safety, and will easily lead to major accidents, thus motorcycle drivers need to enhance their safety consciousness, use your motorcycle in a correct way and do regular and reasonable maintenance for your motorcycle.

Hope these will help you know more about your motorcycle.

Thanks for your time and attention.