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Wednesday, May 3, 2017

BHP Vs Torque

The Very Classic question indeed. What is BHP and what is torque in layman terms ? what is the simple relation between them ? For this, I will include few technical things also in this review to understand it better.

What is torque ? Torque = Force X perpendicular distance.
In layman terms, It is the actual twisting force produced at the crank of an engine due to the power stroke, the potential energy and kinetic energy stored on a flywheel. Consider a 4 stroke single cylinder engine in which the power is actually produced in one stroke, ie the power stroke. In order for the engine to run or the remaining 3 strokes to complete, we should store the excess energy produced by that one power stroke. For that, we have the flywheel.
EX: If you have a 1-foot-long wrench and you exert a force of 10 pounds on the end of it then you apply a torque of 10 pound-feet (10 lb-ft). If the wrench were 2 feet long, the same force would apply a torque of 20 lb-ft. When an engine is said to make “200 lb-ft of torque”, it means that 200 pounds of force on a 1-foot lever is needed to stop its motion.

What is BHP ? BHP = The rate at which work (torque) is done.
In layman terms, its how fast the max torque is produced. So if you increase the weight of flywheel, the engine have to work (rotate harder) to produce that torque. But once done, then the torque will take care of the rest. It will accelerate slower, but have a stable constant speed because of torque. If we reduce the weight of flywheel, the engine will spin more freely and faster, but will produce less torque.
Ex: BHP and torque wont go hand in hand on most occasion. The R&D will decide the characteristic of an engine. Since they are both interconnected, we can give more importance on just one parameter. In sports bikes, we need fast engine speeds which dont give much importance to torque. In a cruiser bike, strong stable speed is more desirable than outright acceleration. For them, Torque is having more importance than BHP.