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

A. Tire Depth Gauge
Minimum Tread Depth

NOTE
Have the wheel balance inspected whenever a new tire is installed.
| WARNING Tires that have been punctured and repaired do not have the same capabilities as undamaged tires and can suddenly fail, causing an accident resulting in serious injury or death. Replace damaged tires as soon as possible. To ensure safe handling and stability, use only the recommended standard tires for replacement, inflated to the standard pressure. If it is necessary to ride on a repaired tire, do not exceed 100 km/h (60 mph) until the tire is replaced. |
NOTE
When operating on public roadways, keep maximum speed under traffic law limits.
Standard Tire (Tubeless)

| 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. New tires are slippery and may cause loss of control and injury. A break-in period of 160 km (100 miles) is necessary to establish normal tire traction. During break-in, avoid sudden and maximum braking and acceleration, and hard cornering. |
Payload and Tire Pressure
BatteryFuel Tank Cleaning
WARNINGGasoline and low flash-point solvents can
be
flammable and/or explosive and cause severe
burns. Clean the tank in a well-ventilated area, and
take care that there are no sparks or flame anywhere
near the working area. Do not use gasoline
or low flash-point solvents t ...
Front Wheel Installation
NOTE
The direction of the wheel rotation [A] is shown by an
arrow [B] on the wheel spoke.
Check the wheel rotation mark on the front wheel and
install it.
Apply high-temperature grease to the grease seal lips.
Fit the collars [A] on the both sides of the hub.
The collars are i ...
Brake Disc Wear Inspection
Measure the thickness of each disc [A] at the point where
it has worn the most.
If the disc has worn past the service limit, replace it.
Measuring Area [B]
Brake Disc Thickness Standard:
Front 5.3 5.7 mm (0.21
0.22 in.)
Rear 4.8 5.2 mm (0.19
0.20 in.)
Service Limit:
Front 5. ...