Enter the motor speed (RPM) and the gear drive output speed (RPM) into the Sheave Ratio Calculator. The calculator will evaluate and display the Sheave Ratio.

## Sheave Ratio Formula

The following formula is used to calculate the Sheave Ratio.

**SHR = MS / GS**

- Where SHR is the Sheave Ratio
- MS is the motor speed (RPM)
- GS is the gear drive output speed (RPM)

## How to Calculate Sheave Ratio?

The following example problems outline how to calculate Sheave Ratio.

Example Problem #1:

- First, determine the motor speed (RPM).
- The motor speed (RPM) is given as: 50.

- Next, determine the gear drive output speed (RPM).
- The gear drive output speed (RPM) is provided as: 20.

- Finally, calculate the Sheave Ratio using the equation above:

SHR = MS / GS

The values given above are inserted into the equation below and the solution is calculated:

SHR = 50 / 20 = 2.5

Example Problem #2:** **

For this problem, the variables required are provided below:

motor speed (RPM) = 60

gear drive output speed (RPM) = 10

Test your knowledge using the equation and check your answer with the calculator above.

SHR = MS / GS** = ?**