Difference Between Torque & HorsePower
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,897
From: Bedford UK
Essentially you only get horsepower once you have torque. As sgdiesel said, at the most basic level Power = Torque x RPM. Torque is the twisting force the engine applies to the driving wheel and the more of it you have the faster it will accelerate the rotation of that wheel.
So torque gets you off the line from standing still and accelerates you ever faster. But the faster you go the more rolling and wind resistance you experience and that requires power to keep you moving. As the torque accelerates you to ever higher speeds, the more power you need to overcome those resistances.
There comes a time when the resistances are so great the engine can no longer accelerate you and you achieve maximum speed. Most Harleys have stock gearing that their maximum speed is pretty low and acceleration is also poor. Reducing ovedrall gearing can improve both significantly, which is probably the most ignored way of improving Harley performance.
Cruiser
Joined: Oct 2009
Posts: 141
Likes: 0
From: Georgia
We seem to have covered pretty well every way of describing these as you requested! Has it helped?
Essentially you only get horsepower once you have torque. As sgdiesel said, at the most basic level Power = Torque x RPM. Torque is the twisting force the engine applies to the driving wheel and the more of it you have the faster it will accelerate the rotation of that wheel.
So torque gets you off the line from standing still and accelerates you ever faster. But the faster you go the more rolling and wind resistance you experience and that requires power to keep you moving. As the torque accelerates you to ever higher speeds, the more power you need to overcome those resistances.
There comes a time when the resistances are so great the engine can no longer accelerate you and you achieve maximum speed. Most Harleys have stock gearing that their maximum speed is pretty low and acceleration is also poor. Reducing ovedrall gearing can improve both significantly, which is probably the most ignored way of improving Harley performance.
Essentially you only get horsepower once you have torque. As sgdiesel said, at the most basic level Power = Torque x RPM. Torque is the twisting force the engine applies to the driving wheel and the more of it you have the faster it will accelerate the rotation of that wheel.
So torque gets you off the line from standing still and accelerates you ever faster. But the faster you go the more rolling and wind resistance you experience and that requires power to keep you moving. As the torque accelerates you to ever higher speeds, the more power you need to overcome those resistances.
There comes a time when the resistances are so great the engine can no longer accelerate you and you achieve maximum speed. Most Harleys have stock gearing that their maximum speed is pretty low and acceleration is also poor. Reducing ovedrall gearing can improve both significantly, which is probably the most ignored way of improving Harley performance.
Grand HDF Member
Joined: Dec 2007
Posts: 4,999
Likes: 55
From: Bay Area
Well heres the way I learned way back in trade school. Torque (turning force usually measured at the flywheel or also at the ground) is what you feel, and makes the vehicle move. Horsepower make the flywheel turn, the more horsepower you make the faster it makes the torque, which moves the vehicle faster.
Road Warrior
Joined: Oct 2009
Posts: 1,384
Likes: 3
From: California
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Road Warrior
Joined: Nov 2007
Posts: 1,940
Likes: 296
From: Wyoming
The Twin Cam is a torque engine and Harley's are all about torque.