Honda CBR250R/RA Owner's Manual page 49

Tread Wear
Replace tyres before tread depth at the
center of the tyre reaches the following
limit:
Minimum tread depth
Front:
1.5 mm (0.06 in)
Rear:
2.0 mm (0.08 in)
(1)
(1) Wear indicator
(2) Wear indicator location mark
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(2)
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