Honda CRF250F Owner's Manual Installation And Operation page 150

Tread Wear
Replace tyres before tread depth (1) at the
centre of the tyre reaches the following
limit:
Minimum tread depth
Front:
Rear:
(1)
(1) Tread depth
3.0 mm (0.12 in)
3.0 mm (0.12 in)
Tube Repair and Replacement
If a tube is punctured or damaged, you
should replace it as soon as possible. A tube
that is repaired may not have the same
reliability as a new one, and it may fail while
you are riding.
If you need to make a temporary repair by
patching a tube or using an aerosol sealant,
ride cautiously at reduced speed and have
the tube replaced before you ride again.
Any time a tube is replaced, the tyre should
be carefully inspected as described on page
24.
25