Yamaha YZ125 2009, Owner'S Service Manual

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3-12
ENGINE
6. Fill:
• Transmission oil
7. Check:
• Oil leakage
8. Check:
• Transmission oil level
9. Install:
• Oil filler cap "2"
ADJUSTING THE PILOT AIR SCREW
1. Adjust:
• Pilot air screw "1"
Adjustment steps:
a. Screw in the pilot air screw until it is lightly
seated.
b. Back out by the specified number of turns.
ADJUSTING THE ENGINE IDLING SPEED
1. Start the engine and thoroughly warm it up.
2. Adjust:
• Engine idling speed
Adjustment steps:
a. Loosen the locknut "1".
b. Turn the throttle stop screw "2" until the en-
gine runs at the lowest possible speed.
c. Tighten the locknut.
CHECKING THE EXHAUST PIPE
1. Inspect:
• O-ring "1"
Damage
→
Replace.
Install the O-rings with their depressed "a" fac-
ing outward.
Recommended oil:
Yamalube 4 (10W-40) or SAE 10W-
40 type SE motor oil
Oil capacity (periodic oil change):
0.66 L (0.58 Imp qt, 0.69 US qt)
Pilot air screw:
2-1/4 turns out
To increase idle speed
→
Turn the throttle
stop screw "2" in.
To decrease idle speed
→
Turn the throttle
stop screw "2" out.