Hydrostatic ATV

countrybrianf · Dec 30, 2015

What is the torque specs on the motors you are using? I'm researching on making a hydraulic mud utv to be more dependable. I'm tired of breaking axles. haha

4570Man · Dec 30, 2015

Motors designed for a toy lawn mower might not work, but a real ZTR is 1200 pounds plus. A ZTR will run 12-20 MPH. I'm guessing you don't need to go that fast and could gear it down for greater toque. A skid steer would be a good place to start. I had an old skid that was sold for scrap, but first I pulled the all the hydraulics, and the motor out of it. The SS I tore down only had one motor per side and used chains to drive both wheels at the same rate. I could get a couple pictures of the SS drive train if you would like.

Renze · Jan 1, 2016

countrybrianf said:
What is the torque specs on the motors you are using? I'm researching on making a hydraulic mud utv to be more dependable. I'm tired of breaking axles. haha

Generally, hydraulic motors have trouble generating torque from standstill because they have dead points. Like trying to take off on a bicycle with the pedal crank fully vertical: You can stand on it, but drop on your side before taking off.

Danfoss OMS motors (and their Eaton, Brevini, M&S equivalents) are orbit motors that have great startup torque for their displacement volume, and tapered roller bearings incorporated. the OMSW version is built extra compact, with its mounting flange put further to the center of the motor to move the bearings to the center of the wheel without the tire hitting the frame.

https://www.hydra.dk/store/hydra/en/product/2273687

bigdeano · Jan 1, 2016

Don't see that anyone has mentioned it, but you can buy two speed hyd motors if you want two speed ranges.

Renze · Jan 2, 2016

bigdeano said:
Don't see that anyone has mentioned it, but you can buy two speed hyd motors if you want two speed ranges.

variable displacement pump would be a better solution for a reasonably high speed vehicle like an ATV

countrybrianf · Jan 3, 2016

Found a website about this project. Has specs on the hydraulic motors. I think they will have plenty of power to do what you want. I'm looking to spin 34.5" Outlaw mud tires.

ATV