Ok, so I've been trying to sell my 2014 Honda CB1100, not because it's bad, but because it is the least great among my 4 motorcycles. But today I found out that it has 65.6 lb/ft of torque. I had assumed that my inline 3, 2007 Triumph Sprint ST to be the champion on torque between it and 4 cyl rivals, but while it's 125 hp obviously blows away the CB on horsepower, its 56.8 lbs of torque pails in comparison, ON PAPER THAT IS! I bring up the concept of paper because on paper my newest bike, a 2016 BMW R1200R has boatloads of torque on paper, but somehow my 2007 Sprint feels more confident, like I guess it can use its small torque better.
Well, I look forward to comments and if anybody wants to buy my reasonably well taken care of 2014 Honda CB1100!
THANKS,
StreetShark
I'll weigh in.
People talk so much about torque, but it literally doesn't matter at all. It's a footnote. Horsepower is what accelerates your bike, period. Now I kinda worry about starting a religious war, but there it is.
Good luck with sale!
If you want to talk HP and torque you're on the wrong site. This is the CB forum. We're about RLETs and replacing our silver side covers.
Torque is the rotational analogue of force, if I remember my physics correctly. That means it is what causes rotational acceleration. But torque is achieved from horsepower and gearing. Horsepower is more fundamental.
But an engine with smaller drivetrain mass could have better acceleration than one with larger, even though it has less torque than the larger bike.
Torque makes you go... Horsepower makes you go fast.
(08-05-2017, 12:58 PM)postoak_imp Wrote: [ -> ]Torque is the rotational analogue of force, if I remember my physics correctly. That means it is what causes rotational acceleration. But torque is achieved from horsepower and gearing. Horsepower is more fundamental.
But an engine with smaller drivetrain mass could have better acceleration than one with larger, even though it has less torque than the larger bike.
You are misinformed my son.
Torque is the force that is generated in the engine by the connecting rods turning the crankshaft. Horsepower is calculated by multiplying torque and rpm/5252. This is why they ALWAYS cross paths at that rpm on a dyno graph and why hp will always rise as RPM increases even if torque remains constant.
If you have ever seen a graph where they don't cross there, then whomever made it created it not knowing how things work.
Horsepower is a term that was coined so that laymen could understand how much work a machine could do when replacing a horse. "This tractor can do the work of 8 horses!!!"
As a side note....did you know that a horse actually produces about 4 horsepower? Go figure.
Horsepower is measured at higher RPM's and torque is the low-end “grunt” or low RPM pulling power of an engine. Diesel engines only make around 300-400HP in those big rigs, but they make anywhere from 1,500 - 2,000 Ft. Lbs of torque, which is what pulls the 80,000 Lbs of payload in a fully loaded big rig.
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I've never seen a good visualization of the torque vs. HP issue. Randy B. is correct in his explanation.
The way I look at it is viewing torque as the force that the engine can apply to the crankshaft (and ultimately the rear wheel) in one revolution of the engine. Horsepower would be determined by the number of times an engine could repeat that performance over time (i.e RPM).
So, if you have two engines, one with a lower torque spec, it can still achieve a higher horsepower number by spinning the engine faster (i.e. applying that torque more times over a given span of time) than the engine that makes more torque.
According to the dyno graphs I've seen, the stock CB1100 produces peak horsepower at around 7300 rpm. Since the Sprint ST has a lower torque value, then it's safe to assume that the rpm at which it produces its greater peak HP value is at a substantially higher rpm than 7300.
Because of this mathematical relationship between torque and HP, it can also be safely assumed that the Sprint ST produces less horsepower at 7300 rpm than the CB1100.
The only flaw I see in Randys explanation is " horsepower will always rise as rpm increases" and that is not true. Most often the hp decreases in the far reaches of the rpm band having peaked earlier, often well before redline. The horsepower graph often looks like a lopsided mountain a long rise, a peak and a short drop off after the peak. If peak hp is at 10,000 and drops off after that, and redline is at 13,000, there is little need to rev to redline, since at that point, you are actually losing power. That's why they invented shift lights, to tell riders when is the optimum time to shift to take advantage of maximum horsepower.