Yamaha YZF-R125 Service Manual: Installing the primary drive gear and balancer gears
1. Install:
- Balancer driven gear "1"
- Lock washer
- Balancer drive gear "2"
- Primary drive gear
- Washer "3"
- Balancer driven gear nut
- Primary drive gear nut
NOTE:
- Align the punch mark "a" in the balancer drive gear "2" with the punch mark "b" in the balancer driven gear "1".
- Be sure to install the washer so that its sharp edge "c" is facing the primary drive gear.
2. Tighten:
- Balancer driven gear nut "1"
- Primary drive gear nut "2"
NOTE:
- Place the aluminum plate "a" between the balancer drive gear "3" and the balancer driven gear "4", and then tighten the balancer driven gear nut.
- Place the aluminum plate "b" between the balancer drive gear "3" and the balancer driven gear "4", and then tighten the primary drive gear nut.
3. Bend the lock washer tab along a flat side of the nut.
Checking the balancer gears and primary drive gear
1. Check:
Balancer drive gear
Balancer driven gear
Cracks/damage/wear Replace.
2. Check:
Primary drive gear
Refer to "CHECKING THE PRIMARY DRIVE
GEAR" on page 5-43.
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Crankcase
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Other materials:
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
To check the drive chain slack
Place the motorcycle on the sidestand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
Shift the transmission in ...
Checking the coolant level
1. Stand the vehicle on a level surface.
NOTE:
Place the vehicle on a suitable stand.
Make sure the vehicle is upright.
2. Check:
Coolant level
The coolant level should be between the
maximum level mark "a" and minimum level
mark "b".
Below the minimum level mark → Add t ...
Checking the clutch springs
The following procedure applies to all of the
clutch springs.
1. Check:
Clutch spring
Damage Replace the clutch
springs as a
set.
2. Measure:
Clutch spring free length "a"
Out of specification Replace
the clutch
springs as a set.
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