Honda CRF250F Owner's Manual Installation And Operation page 202

Do not depress the brake pedal when the
wheel is off the motorcycle. The caliper
piston will be forced out of the cylinder with
subsequent loss of brake fluid. If this occurs,
servicing of the brake system will be
necessary. See your dealer for this service.
Avoid getting grease, oil, or dirt on the disc
or pad surfaces. Any contamination can
cause poor brake performance or rapid pad
wear after reassembly.
Installation
1. Reverse the removal procedure. Install
the side collars into the wheel in their
original locations. Carefully fit the brake
disc between the pads to avoid
scratching them. Make sure the lug (4)
on the caliper bracket (5) is located in
the slot (6) in the swingarm. Check that
the chain adjusters are installed properly.
2. Tighten the rear axle nut to the specified
torque.
Rear axle nut torque:
108 N·m (11.0 kgf·m, 80 lbf·ft)
3. Apply the brake several times and check
for free wheel rotation after the brake
pedal is released.
If a torque wrench was not used for
installation, see your dealer as soon as
possible to verify proper assembly.
Improper assembly may lead to loss of
braking capacity.
(4) Lug
(5) Caliper bracket
(5) (4)
(6)
(6) Slot
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