As the tire tread wears down, the tire becomes more susceptible to puncture and failure. An accepted estimate is that 90% of all tire failures occur during the last 10% of tread life (90% worn). So it is false economy and unsafe to use the tires until they are bald.
If any measurement is less than the service limit, replace the tire (see Tire Removal/Installation in the Wheels/Tires chapter).

Tread Depth Standard:
Front 3.6 mm (0.14 in.)
Rear 5.3 mm (0.21 in.)
Service Limit:
Front 1 mm (0.04 in.) (AT, CH, DE) 1.6 mm (0.06 in.)
Rear 2 mm (0.08 in.) (Up to 130 km/h (80 mph)) 3 mm (0.12 in.) (Over 130 km/h (80 mph))
| WARNING Some replacement tires may adversely affect handling and cause an accident resulting in serious injury or death. To ensure proper handling and stability, use only the recommended standard tires for replacement, inflated to the standard pressure. |
NOTE
Wheel/Tire Damage Inspection
Wheel Bearing Damage InspectionShift Pedal Installation
Install the rubber damper to the shift pedal.
Turn the chamfered side to inside.
Assemble:
Shift Lever [A] and Locknut [B] (Left-hand Thread)
Shift Pedal [C] and Locknut [D]
Tie-Rod [E]
Turn the grooved end [F] of the tie-rod to the shift lever.
Apply grease to the sliding ...
Front Caliper Removal
Remove:
Bolt [A]
Front Wheel Rotation Sensor [B]
Loosen the banjo bolt [C] at the brake hose lower end,
and tighten it loosely.
Unscrew the caliper mounting bolts [D], and detach the
caliper [E] from the disc.
NOTICE
Do not loosen the caliper assembly bolts [F]. Take
out only ...
Rear Sprocket Warp Inspection
Raise the rear wheel off the ground with the stand so that
it will turn freely.
Set a dial gauge [A] against the rear sprocket [B] near the
teeth as shown in the figure, and rotate [C] the rear wheel
to measure the sprocket runout (warp). The difference
between the highest and lowest di ...