DAELIM ET-250 Service Manual page 136

Before loosening castle nut, you have to remove cotter pin
Then using the power tools to take the screw out
from brake stopping plate. You can take the brake disc off.
When change brake shoe wear, you must push
the master piston to rearward.
After removal the front brake assembly, you must fabricate
in reverse sequence.
Wheel hub
Castle nut