I take off the front cover with the rotor, and the plate that covers the rear bearing.
Take bearing out of cover and motorhouse.
then you must clean the bearing's as one would do like usual.
Check bearings for play and if it still runs as it should, if bad replace with new one.
the can along with the winding and sensor stuff inside you better not use motor spray, just air to blow out the dust.
Rotor's dont get messy to much, if it is i'd guess a paper towel is be best.
After that reassemble with caution not damaging anything and check for free rotating on the shaft.
A racecar is only as good as the mechanic who build it.