# Torque Required to turn a wheel

1. Jul 22, 2016

### lysolmax

Hello,

I am trying to figure out how much weight a particular motor/wheel setup can handle.

I have an electric motor that puts out 6000ft*lb of torque, and is driving 44" wheels and needs to reach a maximum of 2RPM. Acceleration doesn't really matter so long as the wheels are able to get up to speed in a reasonable amount of time.

How much weight am I capable of handling on this setup?

2. Jul 22, 2016

### Mech_Engineer

You limitations will be in the inertial of whatever wheel you are accelerating, and the load ratings for the bearings supporting the wheel. 6000 ft-lb of torque sounds like a lot, are you sure you're right on your number there?

3. Jul 22, 2016

### jack action

Rolling Resistance + ma = Driving Force​
$$R_r W + \lambda W \frac{a}{g} \le \frac{T}{r}$$
$$W \le \frac{T}{\left(R_r +\lambda\ ^a/_g \right) r}$$
Where:
In any cases, the Driving Force will not exceed the available friction force ($\mu W$), thus:
$$W \le \frac{\mu W}{R_r +\lambda \ ^a/_g}$$
Or:
$$R_r +\lambda \ ^a/_g \le \mu$$

Where $\mu$ is the tire-road friction coefficient.