Kawasaki Versys Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
84 Posts
Discussion Starter #1
I was surfing a bit earlier today and came across a thread which discussed torque and horsepower, and how to best use them both. It referenced another thread/forum, and I didn't have time to follow up.

Now, I can't find it! Can someone please help me out?

Thanks in advance.
Richard
 

·
Registered
Joined
·
135 Posts
I was surfing a bit earlier today and came across a thread which discussed torque and horsepower, and how to best use them both. It referenced another thread/forum, and I didn't have time to follow up.

Now, I can't find it! Can someone please help me out?

Thanks in advance.
Richard
turn the throttle:yeahsmile:
 

·
Registered
Joined
·
3,427 Posts
HP = ( torque * RPM )/5252

Torque is a rotational force at an instant in time, HP is the work that force can do over a measured interval of time, like accelerate a motorcycle. When it comes to max acceleration, max HP and weight are the only thing that matter. A bike that produces torque at lower RPMs however will however also produce more HP at lower RPMs, which will make it seem more powerful than it actually is. It will also allow the rider to accelerate quickly without ringing out the throttle. This is why some designers, like the designers of the Versys engine sacrifice max torque at upper RPMs ( which means a higher max HP figure) to produce more torque at lower RPMs ( which means the engine will produce more HP than it would otherwise at mid throttle).

http://en.wikipedia.org/wiki/Horsepower

http://en.wikipedia.org/wiki/Torque
 

·
Registered
Joined
·
1,608 Posts
Torque is what pushes the bike down the road. Torque is what a dyno measures. It is converted to horsepower. If you look at the torque curve it peaks at about 43 lb/ft at 7,200 and then drops off gradually to redline. To find out how much power is being put to the road take the torque and multiply it by the gear ratio. In first it is 2.438 in second 1.714. The trick is to find when the torque to the ground in second is greater than in first.
 

·
Registered
Joined
·
84 Posts
Discussion Starter #5
Walter,
I believe you are hitting on the info that I was trying to find. I rebuilt the engine in my first motorcycle, with my father, over 50 years ago, and built many engines for desert racing bikes, back in the day. For the past couple years I have been reading Race Engine Technology magazine to keep abreast of what is going on these days.

I saw a youtube video of Vettel coaching his race engineer who was driving the simulator, and Vettel told him more than once to "use all the revs". Personally, I like finding the spot where torque is doing "it's thing" without excessive rpms. The study you refer to seems to bring all of the aspects into light.

Can you expound a little more or lead me to the thread?

Thanks,
Richard
 

·
Registered
Joined
·
1,608 Posts
Complicated subject and I'm still learning.

Torque = Bench press how much can you press
Horsepower = How many reps can you do

300 lbs x 1 rep lets call it 300 hp
30 lbs x 10 reps 300 hp

From a physics standpoint it doesn't matter if you move the weight all at once or over time, the same work was performed.

If you look at the torque curve of a engine produced by a dyno the torque sharply increases to a point and then tapers off. On a diesel engine this peak comes early, on a gas engine much later. The peak measures the point in the rpm range the engine is operating most efficiently, getting the most power per stroke. On a motorcycle (or car) this is the point you will get you maximum acceleration without changing gears. On the Versys it is about 7,200 rpm.

Think of the gearshift as a torque multiplication selector. When you are in 1st you are multiplying the torque to the rear wheel by 2.438 times. The trick lies in finding the spot in the torque produced to the rear wheel is less in first multiplied by 2.438 than it is in second multiplied by 1.714. There is no point like that so you are limited by the redline, rev limiter at around 10,500. You shift to 2nd at 10,500 and your rpms drop to 7,400.

Now you are comparing the torque produced to the rear wheel multiplied by 1.714 (2nd) to the torque produced to the rear wheel multiplied by 1.333 (3rd). The spot where the torque to the rear wheel in 3rd exceeds the torque to the rear wheel in 2nd comes at about 9,500 rpm, at around 9,200 in 3rd, around 9,000 in 4th.

Have I put you to sleep?
 

·
Registered
Joined
·
3,519 Posts
When you run to the bathroom in the morning to pee and when you do it pushes you against the wall thats torque! ;)
 

·
Registered
Joined
·
84 Posts
Discussion Starter #8
Walter,
Thanks for that info. I will let all of that settle a bit and play with some of the numbers if I have a chance. I understand the theory of it I guess, but I also know that in practice it may be something else.

One example that comes to mind are comments many folks make about Ryan Villapoto and his riding style. It is said that you can tell him by sound from the others because his rpm's are lower.

Thanks again Walter,
Richard
 

·
Premium Member
Joined
·
16,142 Posts
When you run to the bathroom in the morning to pee and when you do it pushes you against the wall thats torque! ;)

:funnypost:
 

·
Super Moderator
Joined
·
19,121 Posts
When you run to the bathroom in the morning to pee and when you do it pushes you against the wall thats torque! ;)
WRONG. Torque is when you run to the bathroom in the morning to pee and when you push DOWN on it for aiming purposes... it takes your legs out from under you! THAT'S TORQUE!!!

;)
 

·
Registered
Joined
·
1,267 Posts
WRONG. Torque is when you run to the bathroom in the morning to pee and when you push DOWN on it for aiming purposes... it takes your legs out from under you! THAT'S TORQUE!!!

;)
Torque could also apply while sitting down to have a **** and when you push, it lifts you off the seat. :eek:
 

·
Registered
Joined
·
1,407 Posts
I can't add anything funnier about sh*t and pi*s VS torque ...
But I can say that if you ride your engine in a powerband that's between max torque and max hp, you will fully enjoy said engine

LOP
 

·
Registered
Joined
·
1,608 Posts
I seldom get there. Around town I usually shift before 4,000. On the highway I cruise at 5,200 (70 mph with 16/46 gearing). When I am in a hurry, I'm in a big hurry.
 

·
Registered
Joined
·
3,519 Posts
WRONG. Torque is when you run to the bathroom in the morning to pee and when you push DOWN on it for aiming purposes... it takes your legs out from under you! THAT'S TORQUE!!!

;)
Thats what ive been trying to tell the wife why i sometimes miss the target :eek:
LOL! These concepts are complicated! :eek: I stand corrected! ;) :D
 

·
Registered
Joined
·
1,608 Posts
Middleweight vs heavyweight... Heavy with more traction wins the tug of war.
Yes, a contest of traction. With equal traction steam engine with 1000 lb/ft of torque and 18 hp and tactor with 500 lb/ft of torque with 2:1 transmission would be even if the tractor could get the rpm up to max torque range.
 
1 - 19 of 19 Posts
Top