Brushed motor maintenance?

[Airdog2000]

Hi all,

I have an older ebike (DIY project that I purchased) with a rear hub brushed motor. I recently replaced the controller (36v 30a) as well as the batteries. The bike goes a maximum of 22 km/hr under its own power on a level road. The motor is at least 12 years old, and I don't have any other info about it (no labels or markings on the outside).

Should I open it up and replace the brushes? Would this increase its power? Is there any other maintenance I should do for a brushed motor (such as lubricating bearings)?

Thanks in advance!

 

[indianajo]

I've worked on brushed DC motors in the factory. Brushes have to be inspected periodically to make sure they are long enough. If they wear too short, the motor runs fine on the springs until the metal to metal wear bridges the copper across the mica insulator of the commutator. Then the motor is trash. Now brushes do not increase power, only increase life.
If you haven't had a failure to perform because the brush did not push in when it was worn, you are very lucky. Removing the cover & snapping the brush spring was very common on Monday morning startup for motors that wouldn't move without help.
Bearing lube depends on design. I haven't taken one of these apart to see what is in there. The brushless motors have cheap ****ese copies of real industrial sealed bearings like the 6001 & 6003.

 

[Airdog2000]

I've worked on brushed DC motors in the factory. Brushes have to be inspected periodically to make sure they are long enough. If they wear too short, the motor runs fine on the springs until the metal to metal wear bridges the copper across the mica insulator of the commutator. Then the motor is trash. Now brushes do not increase power, only increase life.
If you haven't had a failure to perform because the brush did not push in when it was worn, you are very lucky. Removing the cover & snapping the brush spring was very common on Monday morning startup for motors that wouldn't move without help.
Bearing lube depends on design. I haven't taken one of these apart to see what is in there. The brushless motors have cheap ****ese copies of real industrial sealed bearings like the 6001 & 6003.

Amazing, thanks so much! Will open it up and take a look.