
As you may or may not know, we would like to explain how the clutch works and Yamiya's clutch kit.
➊About the clutch
What is the clutch …??
The power generated by the engine is transmitted to the transmission (gears), or disconnects it. What is called a "Power transmission system" More specifically, it has such a following role.
-
Smoothly transmits engine rotation to gears.
-
Temporarily disconnects the power when stopping or starting.
-
Reduces shocks during gear shifting for smoother acceleration.
It is an "essential" part for controlling the power transmission of a motorcycle.
➋How the clutch works
CB750Four has 『Clutch lever』 『Spring』 『Clutch plate』 『Friction disc』When you squeeze the clutch lever, the spring is compressed.
The plates and discs then separate and the power is cut off. This is what is called "neutral”.
Conversely, when you release the clutch lever, the spring returns to its original state, the plates and discs stick together, and power is transmitted to the gears.
➌Yamiya's clutch kit
Yamiya sells three types of clutch kits.
Let's briefly explain the differences between them!
The grooves in the friction disc are diagonal just like the original.
The spring is also the original type. If you are not sure which one to choose, we recommend it.
Many people imagine a light clutch from the name. But it is not a light weight product the problem of it being difficult to shift into neutral.
The friction discs have a lot of vertical grooves. Increasing the number of grooves improves oil penetration and makes it easier for the discs to separate from each other.
The spring is the same as genuine type. We would like to recommend it for those who have trouble shifting into neutral.
The grooves in the friction disc are diagonal just like the original. But the length of the spring is longer than the original type. At high speeds, a strong centrifugal force acts on the clutch.
This can cause the clutch to slip. To suppress centrifugal forces as much as possible, the springs are lengthened and reinforced.
We recommend this to anyone who has customized the engine, such as bore up engines.
For your information…


Yamiya’s clutch kit is included 4 plain clutch plates and 2 clutch plates with dots. This is to make it easier to separate the each clutch plates.
We recommend that placing the dots clutch plates in the center (3rd or 4th) where it is difficult to reach oil.
➍Lastly
Although it was simple, this time I introduced you to the clutch.
The clutch is an important role in transmitting power in a motorcycle, and proper operation and maintenance affect riding performance and safety.
Also, clutch plates and friction discs are consumable items, so regular maintenance and replacement is recommended. I hope you find this article useful, and you will purchase a clutch that suits your CB750Four.