In manual transmission cars some drivers partially press down on the clutch pedal to make the engine operate more smoothly
Some drivers even have the habit of resting their foot on the clutch pedal. This is known as riding the clutch however
You know that this habit is really bad for your car
In order to understand how a partially pressed clutch can help the engine operate more smoothly
but also why this habit can damage your car we first need to learn the basics of the operation of an internal combustion engine and
also of the clutch
The engine is the muscle of a car it produces the necessary driving force to move the vehicle
It should be noted that the torque produced by an internal combustion engine varies depending upon the engine speed
In normal driving conditions the drive force produced by the engine is more than or equal to the forces resisting the motion of the car
However what happens if the resistance is greater than the drive force at the wheels
This will cease the motion of the engine and the engine will stall
Fortunately in a car. There is a mechanism to overcome this imbalance between the forces
the transmission
At the transmission output, you can easily get different speeds by using the gear stick
Since the power produced is the product of torque and angular speed?
By reducing the output speed you will be able to get higher torque or vice-versa
In short whenever the vehicle requires more torque or the supply of torque from the engine is too low
you have to drop to a lower gear
Let's see an example of both cases
To climb this hill the vehicle needs high torque
This is the reason why you use a lower gear on a hill otherwise the engine will stall
When the engine rpm is too low the torque supplied by the engine will also be too low
This happens when a car starts
so to get high torque at the wheels you have to start the vehicle in a low gear
This avoids the engine stalling when the car starts
This is the professional way to avoid an engine stall
Whenever the torque requirement is high or the torque supply is too low
you have to shift to a lower gear
Some drivers however avoid stalling the engine without changing gear
They just partially press the clutch pedal
To learn how they do this let's look at how a clutch works
The clutch sits between the engine and the transmission
Basically a clutch is a mechanism to discontinue the flow of power from the engine to the transmission
In a manual transmission
gear changes can only happen when there is no power flow to the transmission
And by pressing the clutch pedal
you make sure that the power flow is discontinued
Now back to the clutch technique
consider this situation
Here the driver is operating the vehicle in a high gear, but with a low engine speed
The torque supplied by the engine is low due to the low engine speed
and in addition due to the high gear selected
the torque does not get amplified
this situation will definitely lead to an engine stall
Instead of using a lower gear the driver presses the clutch pedal partially
This means that the engine is partially disengaged from the transmission
and the load on the engine is greatly reduced
This instantly saves the engine from stalling
Now whilst keeping the clutch pedal partially pressed
he presses the accelerator pedal further
This takes the engine speed up to a higher torque level
and now he can release the clutch pedal
Thus he has prevented the engine stalling without changing down a gear
the driver was riding the clutch during this operation
Even though this seems like a smart technique
Riding the clutch is not good for your car.
Let's see why
In a clutch, motion from the flywheel is transferred to the transmission with the help of a friction disk
When a good external force is supplied to the disk
the motion from the flywheel will be transferred to the transmission
due to adequate frictional force
a pressure plate spring mechanism provides this external force
As long as you don't press the clutch pedal
the spring mechanism will be supplying a strong external force
When you press the clutch pedal down completely
the pressure plate will move away from the disc with the help of a diaphragm spring
Thus, the transmission will be separated from the flywheel
In short, when you don't press the clutch pedal
the friction discs and flywheel will move together
and when you press it completely
the friction discs and flywheel will be separated
But what if you only press the clutch pedal partially
This will reduce the frictional force between the flywheel and the friction disc
and relative motion happens between them
This will definitely result in wear and tear of the disc
This is why when driving a manual transmission vehicle
you should either press the clutch pedal down completely or you should not press it at all
partial depression of the clutch pedal
will damage the friction disc and the flywheel very quickly
In certain situations, it is impossible to avoid driving the clutch
However, in the situations listed here
you can definitely avoid this operation
Please be one of our patrons
and next time when you are driving try to avoid partially depressing the clutch pedal.
Thank you