Do I Need the Capacitors on back of Brushed Motor?

I've never heard of breakin in water. I'm familar with cleaning a well used brushed motor by running at low voltage in distilled water. You'd be surprised at how much gunk comes out - use a big shot of nitro cleaner and re-oil everything. Usually used on a motor thats gone downhill in an attempt to get some of it back. I've had mixed results.

Breakin - I use my Ice charger