Torque & Horsepower Explained | GTAMotorcycle.com

Torque & Horsepower Explained

I bought a bike this year that has more than enough of both, and honestly that's all I really care about. A little excess is just enough.

OK OK yes a lot of people don't understand the two or how they relate. The primary thing to remember is that horsepower isn't a thing, it's an algorithmic expression of how much work the motor (its twisting force aka torque ) can do (either at a given RPM or at its peak). It's better to make more torque at higher RPMs than lower RPMs if you are looking for performance, because then you gear your final drive to put more of that torque to the pavement. However, not all people want that.

Will probably watch the video, although I have an excellent understanding of this. Interestingly enough, there are more things to consider than torque and horsepower. Breathing efficiency and reciprocal weight can have sizable effects on the engine's ability to accelerator or decelerate and those can make all the difference in a motorcycle and how it works in practical use.
 
It's easy.
Torque is a rotational force, and is measurable
Horse power is a stupid made up number so James Watt could sell steam engines to farmers too stupid to know what rotational force is. (Watt said his motor could do the work of 4 horses... so it was a 4 HP motor) (An average horse has about 15-18 HP, a Clydesdale as much as 30HP)
Horse power is torque/time. Torque is how much power right this second. HP is how much torque spread over how much time... torques (ft/lbs) per minute
People SAY they want HP, but they really mean they want torque. Torque pushes you into your seat on acceleration, torque pulls you out of corners, applied torque = acceleration
Torque gets you to speed, HP keeps you there
Unless you're doing landspeed runs, HP is a pretty useless measurement... BUT IT SELLS BIKES... cuz most of us are too stupid to know what rotational force is... and what it does (mostly what advertisers say is HP is actually a function of torque... seeing how HP IS torque).
 
Horsepower is very useful in racing (and general performance). Yes it's a weird math function but looking at a graph of horsepower output, one can determine both where the power output falls off enough to shift optimally and where to gear the final drive for the purpose of the vehicle - accelerative performance, towing or top speed.

Of course gearing will always be a compromise of some sort but luckily we have different vehicles for different purposes.
 
To the GTAM residents with the most life experience: what was the first time you can remember reading or hearing something trying to explain horsepower vs torque in writing?

For me it was almost certainly a Hot Rod magazine, I'm gonna roll the dice and say I was approximately 12
 
TwistedKestrel said:
To the GTAM residents with the most life experience: what was the first time you can remember reading or hearing something trying to explain horsepower vs torque in writing?

For me it was almost certainly a Hot Rod magazine, I'm gonna roll the dice and say I was approximately 12
Click to expand...
Grade 8.
 
I remember being about 12 and having a guy try to explain to me why he'd spent $4400 of 1971 dollars for titanium wheel lugs for his top fueler...but only for the rear wheels
I'm glad he took the time.
 
Simplistically, horsepower is how fast you get to the wall, torque is how much you move it when you hit.
 
TwistedKestrel said:
To the GTAM residents with the most life experience: what was the first time you can remember reading or hearing something trying to explain horsepower vs torque in writing?

For me it was almost certainly a Hot Rod magazine, I'm gonna roll the dice and say I was approximately 12
Click to expand...

Same, was a car guy long before I became a motorcycle guy and I remember reading it in a car magazine when I was a kid.
 
My biggest lesson on torque came from an old WWII Italian mechanic Luigi Meneghetti. He taught me a lot of mechanical stuff and techniques. One unique think he believed was a mechanic know how to feel torque. After making me tightening and check thousands of fasteners, I learned how to be my own torque wrench.

I use torque wrenches today, but don’t really need them.
 
i learned early on that there were Japanese horses and there were German horses. The German horses had more torque.
 
TK4 said:
I hope you still do - installing crankshaft main and rod bearings or cylinder heads for instance is not a 'done by feel' thing.
Click to expand...
I use torque wrenches, but I still test myself.

The old fella that taught me as a kid was used to field work with limited tools. Being your own torque wrench was a skill for him.

Times change.
 
  • Like
Reactions: TK4
Here's what I know: After owning a KLR you realize how over rated horse power is.
 
  • Haha
Reactions: TK4
A cbr125 has no torque anywhere in its power band, but below 7000 rpm you're not going anywhere, and past 10000 rpm it's not going any faster.
 
  • Haha
Reactions: TK4
TK4 said:
13 hp is only going to get you so far...
Click to expand...
Were you not listening? It might get you around the world twice but 13hp is only going to get you so FAST.
 
  • Haha
Reactions: TK4
timtune said:
Were you not listening? It might get you around the world twice but 13hp is only going to get you so FAST.
Click to expand...
I rode one from Calabogie to T.O.
It took me over 6 hours, the poor little blighter was pinned all the way but never missed a beat.
It was either that or walk.
 
You must log in or register to reply here.

Back
Top Bottom