Problem: Loud grinding noise coming from Loona’s robotic legs.
It can be caused by either of the following things:
Loona motor grinding noise cause #1.
The gear on the central peg might have moved out of place due to vibrations from Loona’s movements and has slipped, causing the gear on the central peg to skip over the moving gear components and that explains the loud grinding noise.
Solution: Gently hammer the central peg back into place.
Loona motor grinding noise cause #2. Central pin has a groove that erodes over time and snaps.
Solution: Replacement with new motor gearbox.
Loona motor grinding noise cause #3.
Gears breaking due to teeth snapping. Small gears unable to bear the heavy loads placed on them.
Solution: Replacement with new motor gearbox.
Loona motor grinding noise cause #4.
The black plastic mount inside the leg has broken; the screws exert excessive pressure on the black plastic mount and it has broken causing the motor and gears to move out of position.
Solution: Replacement of black plastic mount with 3D printed part.
Black Mount Part Source: Pending. Note this 3D printed part needs to be slightly modified to fit Loona’s specifications.
Motor Gearbox Specifications for Loona PetBot Robot:
• N20 12v 60rpm motor gearbox.
•Requires a 104 capacitor.
•Voltage: 12v
•Revolutions Per Minute: 60rpm
Unofficial Motor Gearbox Modification Tips:
•The D post needs to be filed. The 10mm shaft is not D shaped so requires filing.
• Threading the post may not work. The tip is threaded, so any part requires a die to put the thread on.
•Try drilling a 1/16 hole and using a finishing nail to retain the gear or try installing it using a set collar.
•You can try installing it using a set collar. You will need to file the gearbox to fit and it also involves cutting the plastic housing.
•The replacement gearbox won’t fit the mounted motor. You have to replace the entire motor gearbox with a new one.
•Be careful when navigating the cables of the waist motor assembly. Be aware of the potentiometer/position switch/end-of-stroke switch.
Compatibility: New gearbox might not fit onto the existing mounted motor; it is suggested to replace the existing motor with a new motor gearbox.
Tip: Insulate any cables in the leg mechanism with protective cable covers to prevent cables near waist motor from being damaged by the black mount or gears.
Selection tip: Ensure the motor gearbox has the same predisposition as the existing central peg/screw.
This is a complex repair and is undertaken at your own risk. Seek the advice of an experienced electronics repair technician in your local area and have them perform the repair for you if possible.
Design flaw? It’s worth noting replacement gear boxes either official or unofficial always fail.
Prevention: Suggest only using Loona in companion mode until KEYi come up with a permanent fix for this.
Disclaimer: Clearly I’m not a technical person and have yet to learn the correct terminology and without photographs a lot of this information is redundant. If any of my Loona develop this issue I will order replacement motors and attempt the repair, providing photographs to match the dialogue.
It can be caused by either of the following things:
Loona motor grinding noise cause #1.
The gear on the central peg might have moved out of place due to vibrations from Loona’s movements and has slipped, causing the gear on the central peg to skip over the moving gear components and that explains the loud grinding noise.
Solution: Gently hammer the central peg back into place.
Loona motor grinding noise cause #2. Central pin has a groove that erodes over time and snaps.
Solution: Replacement with new motor gearbox.
Loona motor grinding noise cause #3.
Gears breaking due to teeth snapping. Small gears unable to bear the heavy loads placed on them.
Solution: Replacement with new motor gearbox.
Loona motor grinding noise cause #4.
The black plastic mount inside the leg has broken; the screws exert excessive pressure on the black plastic mount and it has broken causing the motor and gears to move out of position.
Solution: Replacement of black plastic mount with 3D printed part.
Black Mount Part Source: Pending. Note this 3D printed part needs to be slightly modified to fit Loona’s specifications.

• N20 12v 60rpm motor gearbox.
•Requires a 104 capacitor.
•Voltage: 12v
•Revolutions Per Minute: 60rpm
Unofficial Motor Gearbox Modification Tips:
•The D post needs to be filed. The 10mm shaft is not D shaped so requires filing.
• Threading the post may not work. The tip is threaded, so any part requires a die to put the thread on.
•Try drilling a 1/16 hole and using a finishing nail to retain the gear or try installing it using a set collar.
•You can try installing it using a set collar. You will need to file the gearbox to fit and it also involves cutting the plastic housing.
•The replacement gearbox won’t fit the mounted motor. You have to replace the entire motor gearbox with a new one.
•Be careful when navigating the cables of the waist motor assembly. Be aware of the potentiometer/position switch/end-of-stroke switch.
Compatibility: New gearbox might not fit onto the existing mounted motor; it is suggested to replace the existing motor with a new motor gearbox.
Tip: Insulate any cables in the leg mechanism with protective cable covers to prevent cables near waist motor from being damaged by the black mount or gears.
Selection tip: Ensure the motor gearbox has the same predisposition as the existing central peg/screw.


Prevention: Suggest only using Loona in companion mode until KEYi come up with a permanent fix for this.
Disclaimer: Clearly I’m not a technical person and have yet to learn the correct terminology and without photographs a lot of this information is redundant. If any of my Loona develop this issue I will order replacement motors and attempt the repair, providing photographs to match the dialogue.