Oil quality is a major contributor to your engine's performance and life. Always select good quality engine oil. Suzuki recommends the use of suzuki performance 4 motor oil or equivalent engine oil. Use sf/sg or sh/ sj with jaso ma in api (american petroleum institute) classification.

Api: american petroleum institute jaso: japanese automobile standards organization
Sae engine 011 viscosity
Suzuki recommends the use of sae 1 ow-40 engine oil. If sae 10w-40 engine oil is not available, select an alternative according to the following chart.

Jaso T903
The jaso t903 standard is an index to select engine oils for 4- stroke motorcycle and atv engines. Motorcycle and atv engines lubricate clutch and transmission gears with engine oil. Jaso t903 specifies performance requ irements for motorcycle and atv clutches and transmission.
There are two classes, ma and mb. The oil container has following classification for confirming the standard.

Energy conserving
Suzuki does not recommend the use of "energy conserving" oi ls. Some engine oils which is api sh or greater has "energy conserving" indication in api classification doughnut mark.
These oils can affect engine life and clutch performance.
Fuel
Engine coolant solutionRear combination light removal and installation
Removal
Remove the frame cover assembly. Refer to “exterior parts removal and
installation” in section 9d .
Remove the clamps (1).
Disconnect the combination light coupler (2).
Remove the rear combination light assembly (3).
Remove the combination light brack ...
DTC “c31” (p0705): gp switch circuit
malfunction
Detected condition and possible cause
Detected condition
Possible cause
No gear position switch voltage
Gp switch voltage is not within the following range.
Gp switch voltage > 0.6 V
Gp switch circuit open or short.
Gp switch malfunction.
...
Front wheel components
Front axle
Brake disc bolt
Brake disc
Dust seal
Bearing
Spacer
Air valve
Front wheel
Wheel balancer
Front tire
Collar
Front axle bolt
18 N·m (1.8 Kgf-m,
13.0 Lbf-ft)
100 N·m
(10.0 Kgf-m, 72.5 Lbf-ft)
Apply ...