I understand Horsepower, but I just dont understand torque.
Can someone give me an explanation in laymens terms (for the dumbass I am).
Cheers,
Bren
I understand Horsepower, but I just dont understand torque.
Can someone give me an explanation in laymens terms (for the dumbass I am).
Cheers,
Bren
Okay, how to explain Torque...
Well, it was a crap movie with quite a lot of sportsbikes. Britney Spears made a song "Toxic" that had nothing to do with the film, but they somehow managed to connect the two.
The main characters were... etc etc.
But seriously, here's an easy-ish explanation, not mine...
Mr Watt made this famous calculation to define the relationship between TOrque and Horsepower.Torque is a twisting force applied to an object, like a wheel or a crankshaft. Note that motion is not required for torque to exist! If you stand on a lug wrench that is on a frozen lug bolt, you are applying a torque to that bolt even though there may be no movement. For our purposes, we will consider that torque is measured in pounds-force feet (lbf-ft) meaning the equivalent of a given force, in pounds, acting on the end of a lever of length in feet. For example, standing with 180 pounds body weight on a lug wrench one foot long yields 180 lbf-ft of torque. A child of 90 pounds standing on a two-foot lug wrench applies the same torque.
Work is the application of force over a distance. Unfortunately, the units used are the same (pounds times feet) but we write this as ft-lb just to distinguish it. The real difference is that in this case, the "feet" part means feet of movement. If you push on a car with 100 pounds of force and maintain that for 30 feet, you have done 3000 ft-lb of work. An easier example is lifting a weight (in pounds) a given distance (in feet). If you use some sort of mechanical advantage, like a winch, you will do the same amount of work because by halving the effort required, you will have to double the distance through which you apply the force to achive the same objective.
Power is the application of work within a finite time. 550 ft-lb of work in one second is one horsepower.
Hp = rpm x torque
...........5,252
But I don't... really understand it properly.
Someone said this, which sums it up quite nicely...I'd like to think that torque is an intuitively easier concept to understand. If that were true, though, then more people would understand the relationship between torque, horsepower, and vehicle acceleration. In reality, none of it is intuitive. If it were, Newton wouldn't be considered the Really Great Guy that he is.
Think of Horsepower as being the source of the push, but Torque as amount of force available to do the pushing.
Time to ride
Power is what comes out of the engine, torque is what is applied at the wheels. Most often demonstrated on race track - power moves the drive shaft and the vehicle forward, torque is what makes the tyres spin and the front end rise.
Torque = position of fulcrum x force acting on the lever.
Think of turning a bolt with your fingers: you don't have much twisting force there, but add a wrench and you multiply the torque applied to the bolt. The longer the wrench handle (lever) the greater the torque.
compliments of my husband.
p.s. (this is the edit) torque is what's required to 'get it going or to accelerate', horse power is what is needed to 'keep it going'. (again, compliments of Rik)
Last edited by PrincessBandit; 10th February 2008 at 11:54. Reason: added
Power (hp) = Torque (ft-lb) * RPM / 5252
- Maximum acceleration at any speed occurs at the HP peak.
- Maximum acceleration in any gear occurs at the torque peak
- HP = torque * RPM / 5252
- torque = HP * 5252 / RPM
- torque = HP at 5252 RPM
Torque is twisting force, also described as a moment. In enigneering applications, moments are summed and balanced to determine forces acting on object *along with other equilibrium equations...but we won't talk about those*. To find torque, most people use a basic formula which force applied multiplied by perpendicular distance from the point of rotation is used to find torque. Thus when the motorbikes rear wheel is spinning there is a torque/twisting force. If the force from the torque *which can be found from the torque and perp distance* is greater than the maximum force that can be applied to the tarmac ,thus exceeding the coefficient of static friction means you get a nice burnout *there is a formula for this where f=mus*N, argh no scientific symbols.
*note: I do not have my eng textbooks at hand, and have not thought bout eng for a few months now, so if there is a mis-wording i'm sorry. Really should get my brain back in uni mode*
torque is the work done, power is the rate the work is done. Do the work faster you have more power.
what NordieBoy said in other words.
okay then...thats all the technical stuff...but for a dumbass like me a bike with lower HP but higher torque is better in the twisties than one with higher HP and lower torque??? The reason I ask this is there are 2 bikes on my mind that keep on popping up as possibilities for later.
One of my criteria is a low seat height (wife suffers from ducks disease)
So here are the specs (hp and Torque) of both. On those details which one is better?
Bike 1: 34HP 40.68 NM @ 3200 RPM
Bike 2: 31HP 45.5 NM @3400 RPM
Both have seat heights at 27 inches...
I know the figures are not flash but I am not a speed freak and dont plan to be going at 150kmh
think of torque as a measure of the ability to accelerate.
it aint horsepower that makes for acceleration, horsepower is merely a measure of work done.
torque is more real world: the higher the torque at any given rev, the more the acceleration available
Well said.
Torque is a twisting/rotational force,generaly speaking Car engines and trucks have large toquey engines to move large heavy loads,5 people plus luggage plus trailers whereas bikes,generaly speaking have high horse power and lower torque to move a lighter object faster.
So a 1000cc two stroke bike with five passengers and a trailer aint gonna move but a 1000cc car will pull that load fairly easily .
A large capacity Harley will pull up a tree stump,torque.A two fifty two stroke racing bike attempting the same feat would disintegrate.
I apologise for the above,it wasn't till I came to write this that I realised how hard it is to explain.
Anyway if you can get a bike with large torque and large power that peaks at similar revs youre on to a winner. I've got a headache now,easier Questions please.![]()
Oh bugger
Sorryyou meant in terms of motorcycles...yeah basically what the others said lol..can a harley really pull up a tree stump?
mate, a "tourquey" bike has say a twenty litre bucket of "force" and a "Revvy" bike has a ten litre bucket of "force"
at 3,000 buckets per minute the tourquey bike is moving twice as much as the revvy bike, but by 5,000 buckets per minute it hits the wall, moving approximately 100,000 litres per minute
the revvy bike can move 15,000 buckets per minute at it's fastest so it can actually move 150,000 litres per minute
tourque being the size of your bucket
power is the work per minute
more buckets per minute = more power!
that's a bloody excellent description FzerozeroT: humour and intelligence in one post, a rare thing
On first instincts I would be inclined to say that bike 2 would be better for the twisties and Bike 1 for outright performance. However looking at where the peak torque comes compared to Revs, it appears that Bike 1 may have the smoother delivery. This is where a dyno chart will give more infomation than raw claims from the manufacturer.
Don't make the mistake of selcting a bike based on HP and torque alone.
Time to ride
There are currently 1 users browsing this thread. (0 members and 1 guests)
Bookmarks