Checking The Shift Drum Assembly; Checking The Transmission; Installing The Transmission - Yamaha YZ250F Owner's Service Manual

CHECKING THE SHIFT DRUM ASSEMBLY

EAS1SM5293
1. Check:
• Shift drum groove
Damage/scratches/wear  Replace the
shift drum assembly.
• Shift drum segment "1"
Damage/wear  Replace the shift drum as-
sembly.
EAS1SM5294

CHECKING THE TRANSMISSION

1. Measure:
• Main axle runout
(with a centering device and dial gauge "1")
Out of specification  Replace the main ax-
le.
Main axle runout limit
0.08 mm (0.0032 in)
2. Measure:
• Drive axle runout
(with a centering device and dial gauge "1")
Out of specification  Replace the drive ax-
le.
Drive axle runout limit
0.08 mm (0.0032 in)
3. Check:
• Transmission gears
Blue discoloration/pitting/wear  Replace
the defective gear (s).
• Transmission gear dogs
Cracks/damage/rounded edges  Replace
the defective gear (s).
4. Check:
• Transmission gear movement
Rough movement  Replace the defective
gear (s).

INSTALLING THE TRANSMISSION

EAS1SM5295
1. Install:
• 5th pinion gear (24T) "1"
• 3rd pinion gear (18T) "2"
• Collar "3"
• 4th pinion gear (18T) "4"
• 2nd pinion gear (16T) "5"
(to the main axle "6")
TIP
Before installation, apply molybdenum disulfide
oil to the inner and end surface of the idler gear
and to the inner surface of the sliding gear, then
install.
1
6
5-71
TRANSMISSION
5
4
3
2
M