What is the working principle of a motorcycle transmission?
2 Answers
The working principle of the transmission is that when the gear shift pedal assembly is stepped on, the shift shaft rotates accordingly, causing the shift arm body S welded to the shift shaft to swing. The shift arm is connected to the shift arm body via a pin and is always pulled upward by a tension spring. Since the other end of the shift arm has a slot, and two positioning pins are located within this slot, the shift arm always presses against the positioning pins under the action of the tension spring. Under the influence of the slot hook, it pulls or pushes the positioning pins to move along the direction of the shift arm's motion. The function of the transmission: During motorcycle operation, as road conditions continuously change, it is necessary to frequently adjust the vehicle's speed and traction accordingly. For example, when driving on flat roads, the vehicle can travel faster, whereas on uneven roads or slopes, due to higher driving resistance, the speed must be reduced to increase the vehicle's traction. The structure of the transmission: Main shaft, secondary shaft, each with six gears of varying sizes, shift forks, and a shift drum.
When riding my motorcycle, I discovered that the core of the transmission is the gear system. The engine transmits power to the transmission through the input shaft. When you pull the clutch lever, the power is temporarily cut off, allowing me to use my left foot to shift the gear lever into different positions: lower gears like 1st provide high torque to the wheels, making it easier to start or climb hills; mid-range gears like 3rd balance acceleration; higher gears like 5th are used for high-speed cruising, saving fuel. Then, by gradually releasing the clutch, the gears engage and power is transferred back to the wheels. When shifting gears, it's essential to find the right engine RPM—too fast or too slow can cause stalling or gear wear. If the transmission feels sticky, checking clutch cable slack or insufficient gear oil is key. After changing the oil myself a few times, I realized the internal structure is quite intuitive, like the gear drum rotating to select positions, which is similar to a car's transmission but more compact.
