Yamaha YZF-R125 Service Manual: Adjusting the drive chain slack
NOTE:
The drive chain slack must be checked at the tightest point on the chain.
| CAUTION: A drive chain that is too tight will overload the engine and other vital parts, and one that is too loose can skip and damage the swingarm or cause an accident. Therefore, keep the drive chain slack within the specified limits. |
1. Stand the vehicle on a level surface.
| WARNING Securely support the vehicle so that there is no danger of it falling over. |
NOTE:
Both wheels should be on the ground without a rider on the vehicle.
2. Turn the rear wheel several times and find the tightest position on the drive chain.
3. Check:
- Drive chain slack "a"
Out of specification
Adjust.
NOTE:
Measure the drive chain slack halfway between the drive axle and the rear wheel axle.
4. Adjust:
- Drive chain slack
a. Loosen the wheel axle nut "1".
b. Loosen both locknuts "2".
c. Turn both adjusting bolts "3" in direction "a" or
"b" until the specified drive chain slack is obtained.
NOTE:
- To maintain the proper wheel alignment, adjust both sides evenly
- Push the rear wheel forward to make sure there is no clearance between the drive chain pullers and the ends of the adjusting bolts.
d. Tighten the wheel axle nut to specification.
e. Tighten the locknuts to specification.
Bleeding the hydraulic brake system
WARNINGBleed the hydraulic brake system whenever:
the system is disassembled.
a brake hose is loosened, disconnected or
replaced.
the brake fluid level is very low.
brak ...
Lubricating the drive chain
The drive chain consists of many interacting
parts. If the drive chain is not maintained properly,
it will wear out quickly. Therefore, the drive
chain should be serviced, especially when the
vehi ...
Other materials:
Starting failures
Engine
1. Cylinder and cylinder head
- Loose spark plug
- Loose cylinder head or cylinder
- Damaged cylinder head gasket
- Damaged cylinder gasket
- Worn or damaged cylinder
- Incorrect valve clearance
- Improperly sealed valve
- Incorrect valve-to-valve-seat contact
- Incorrect valve timi ...
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.
...
Checking the coolant temperature sensor
1. Remove:
Coolant temperature sensor
WARNING
Handle the coolant temperature sensor
with special care.
Never subject the coolant temperature sensor
to strong shocks. If the coolant temperature
sensor is dropped, replace it.
2. Check:
Coolant temper ...