Today’s post is a bit different and informative. Now, I have observed that many people get confused between horsepower and torque. Don’t worry, I’ve been there. Now, the thing is that when people are choosing a car or a bike, when they see the specifications, they do not understand why the power and torque figures are the way they are and what the vehicle is designed to do and good at, by reading the figures. They also get confused as to how will the vehicle really behave in the real world. Well, if you are confused about that, take a long test ride. Now, if you want to understand how power and torque figures work and how they can give a rough idea of how the vehicle will behave in different scenarios, or what the vehicle is designed to do, then continue reading.
So, what is power? Power, basically, is the amount of work done by an object per unit time, or the rate of doing work. Now, this is the definition of power that is taught in physics, but I hear you say that,” Hans, we aren’t here for a boring Physics lecture! How is this even related!?”. Well, to make it easy, power is the maximum amount of work that the engine of a car or bike can do in a given situation. Power also determines how quickly the work can be done by the engine. Power can be measured in many units, but the ones that are most common are horsepower (HP), Kilowatt (kW) and PS, that is short for pferdestarke, which means horsepower in German. Both PS and HP are almost the same. Now, the more the power, the harder the engine can work in order to take the vehicle to higher speeds more effortlessly. Power is required for good top speed. In ICE engines (Petrol and diesel), the peak power, the maximum power that is written in the spec sheet, is produced at a specific rpm (revolutions per minute). You have to accelerate and rev the engine till it reaches the specific given rpm to produce the peak power, the maximum power that the vehicle produces. So that wraps up power. Now, what is torque? Torque is the rotational force generated by the engine that is transferred to the shaft. The shaft moves the car/bike forward. So, in basic layman language, torque is the pulling force, or the pulling power, or the so called “grunt” that pushes the vehicle forward. The peak torque, or maximum torque, is also produced at a specific rpm, that is written in the spec sheet.
Now that we have understood power and torque, let us try to understand what can we predict about the vehicle and how will it behave in different scenarios and what it is designed to do by reading the power and torque figures of the vehicle. For now, I will take some examples. First, let us consider the example of the pulsar NS200(power-24.5 bhp, torque-18.5N.m) and the new pulsar N250(power-24.1bhp, torque-21.5 N. m). Now, what really makes these bikes different is that the NS makes more horsepower, whereas the N250 makes more torque. The NS200 is made for having more top-end performance at higher rpm and more top speed. It is made for pushing it to it’s limit on the wide-open roads and for revving it out completely. Whereas, the N250 has a bit less horsepower but much more torque, since it has a bigger engine and it is designed to be ridden on city streets and in the urban jungle and in traffic situations, where it requires more torque in the low-end and mid-range of the powerband. In simple words, the N250 will pull more quickly from stoplight to stoplight and it does not need to be revved out completely for its power and torque like the NS200. Both motorcycles have almost the same power and torque on the spec sheet, but both motorcycles deliver power differently. The NS200 loves its revs, whereas the N250 makes more low-end grunt and feels peppier in slow-speed city traffic. It is not just about the horsepower and torque, but it is also about at what rpm the peak power and torque is produced.
From this example, we get to know more about what these bikes are meant to do by knowing at what rpm the power and torque is produced and what horsepower and torque is produced. The same example applies to cars, bikes, trucks and whatever uses an engine. The use case of the vehicle really helps in guessing how the vehicle will perform.
