Motor gear ratio explained

Written By Beate Øvland

There are two pulleys and a timing belt connecting the motor and the paddles.

 
 

Depending on your model, the ratio between the two pulleys differs. On nearly all roasters up to p16, we had a 1:1 gear ratio, meaning the two pulleys were of equal size.

 
 

On some p16, we started using a 2:1 gear ratio to get double the torque.

Then we changed to 3:1 for more torque. 3:1 is now standard.

To improve performance with 3:1 gearing, we removed component r25 on the PCB. By removing r25, the setting in the menu must be 12:1. Gear ratio is 3:1, but the firmware needs 12:1.

Check your gear ratio settings in the service menu if you are experiencing issues with the motor, either by a warning message on the touchscreen, odd movements, or sounds from the drum. What gear ratio your machine should have depends on the model (what pulley ratio it has) and if the PCB has the r25 chip or not:

  • 1:1 gearing + r25 on PCB = 1:1 gear ratio in service menu

  • 2:1 gearing + r25 on PCB = 2:1 gear ratio in service menu

  • 3:1 gearing + r25 on PCB = 3:1 gear ratio in service menu

  • 1:1 gearing – (minus) r25 on PCB = 4:1 gear ratio in service menu

  • 2:1 gearing - (minus) r25 on PCB = 8:1 gear ratio in service menu

  • 3:1 gearing - (minus) r25 on PCB = 12:1 gear ratio in service menu

Beate Øvland
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