Air Switching Valve Removal/Installation
Air Switching Valve Inspection
If the air switching valve [A] is normal, check the wiring for continuity (see Air Switching Valve Circuit).
Special Tool - Hand Tester: 57001-1394
If the wiring is good, check the ECU for its ground and power supply (see ECU Power Supply Inspection in the Fuel System (DFI) chapter).
If the ground and power supply are good, replace the ECU (see ECU Removal/Installation in the Fuel System (DFI) chapter).

Air Switching Valve Circuit

1. ECU
2. Air Switching Valve
3. Ignition Switch
4. Joint Connector F
5. Joint Connector A
6. Fuse Box 1
7. Ignition Fuse 15 A
8. Relay Box
9. ECU Main Relay
10. Frame Ground 1
11. Frame Ground 3
12. Starter Relay
13. ECU Fuse 15 A
14. Main Fuse 30 A
15. Battery
16. Engine Ground
Exhaust Butterfly Valve Actuator Resistance InspectionRocker Arm/Tie-Rod Bearing, Sleeve Inspection
NOTICE
Do not remove the bearings for inspection. Removal
may damage them.
Visually inspect the rocker arm, or tie-rod sleeves [A] and
needle bearings [B].
The rollers in a needle bearing normally wear very little,
and wear is difficult to measure. Instead of measuring,
inspect the ...
Shifting Gears
Close the throttle while pulling in the
clutch lever.
Shift into the next higher or lower
gear.
Open the throttle part way, while releasing
the clutch lever.
For smooth riding, each gear position
should cover the proper rate of speed
shown in the table.
WARNINGDownshifti ...
Piston Ring, Piston Ring Groove Wear Inspection
Check for uneven groove wear by inspecting the ring seating.
The rings should fit perfectly parallel to groove surfaces.
If not, replace the piston and all the piston rings.
With the piston rings in their grooves, make several measurements
with a thickness gauge [A] to determine pisto ...