Translating Torque to Pulling Power

  • Thread starter Thread starter Kyle Shobe
  • Start date Start date
  • Tags Tags
    Power Torque
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
5 replies · 4K views
Kyle Shobe
Messages
2
Reaction score
0
I have an atv and wanted to know its towing capacity. I looked up specs and found that the maximum torque is 1.56 kg-m (11.28 ft-lb)/6,000 rpm. 2 questions: 1) What does this mean in layman's terms? 2) What is the towing capacity?
 
Physics news on Phys.org
Without more details where exactly this torque can be gained and how it gets transmitted to the wheels there is no way to tell that. You'll also need details about the thing getting towed I guess (especially its coefficient of friction).
 
Kyle Shobe said:
I have an atv and wanted to know its towing capacity. I looked up specs and found that the maximum torque is 1.56 kg-m (11.28 ft-lb)/6,000 rpm. 2 questions: 1) What does this mean in layman's terms? 2) What is the towing capacity?

Welcome to the PF.

Which ATV is it? Does it not have a manufacturer's specification for the rated towing capacity (GVW & GVTW & Hitch Weight)?

http://www.gmc.com/trailering-towing/safe-trailer-towing-capacity.html :-)
 
Last edited by a moderator:
It is a 1986 Honda 200sx. I found specs online, but nothing about towing capacity...
 
Kyle Shobe said:
It is a 1986 Honda 200sx. I found specs online, but nothing about towing capacity...

Hmm. You might try looking at the specs of a more modern ATV of the same size & displacement. They should be listing GVW and the towing specs for some of them. I don't think the specs would have changed much for similar-size ATVs. :-)
 
Towing capacity and pulling power are different concepts.

Towing capacity will include handling characteristics like propensity to roll over , brakes, and the like .

Pulling power? I think the term is "drawbar pull".
Surely gear ratios are in the specs you found? (Everyplace i looked wanted a credit card.)
Engine torque multiplied by gear ratio gives a slightly optimistic estimate of torque to rear wheels. It's optimistic because there's a few % lost to friction in the geartrain.
That number divided by wheel radius will give a number for how hard the machine could pull provided it has traction and provided the front wheels stay on the ground.
If you use torque in foot-lbs, use radius in feet..

http://auto.howstuffworks.com/auto-parts/towing/equipment/tow-bars/drawbar-pull1.htm
drawbar-pull-2.jpg


note drawbar connection is low on tractor . That helps keep front wheels down when pulling, and helps keep trailer from toppling tractor over sideways on a downhill turn.

old jim