Yamaha YZF-R125 Service Manual
- General information
- Specifications
- Engine specifications
- Chassis specifications
- Electrical specifications
- Tightening torques
- Lubrication points and lubricant types
- Lubrication system chart and diagrams
- Cooling system diagrams
- Cable routing
- Periodic checks and adjustments
- Chassis
- General chassis
- Front wheel
- Rear wheel
- Front brake
- Rear brake
- Handlebars
- Front fork
- Steering head
- Rear shock absorber assembly
- Swingarm
- Chain drive
- Engine
- Engine removal
- Cylinder head
- Camshaft
- Valves and valve springs
- Cylinder and piston
- Generator and starter clutch
- Electric starter
- Clutch
- Oil pump
- Shift shaft
- Balancer gear
- Crankcase
- Crankshaft
- Transmission
- Cooling system
- Fuel system
- Electrical system
- Ignition system
- Electric starting system
- Charging system
- Lighting system
- Signaling system
- Cooling system
- Fuel injection system
- Fuel pump system
- Electrical components
- Troubleshooting
Identification numbers
Record the key identification number,
vehicle identification number and model
label information in the spaces provided
below for assistance when
ordering spare parts from a Yamaha
dealer or ...
General information
NOTICEThis manual was produced by MBK Industrie.
primarily for use by Yamaha dealers and their qualified
mechanics. It is not possible to include all the knowledge of a mechanic
in o ...
Other materials:
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 ...
Checking the connections
Check the leads, couplers, and connectors for
stains, rust, moisture, etc.
1. Disconnect:
Lead
Coupler
Connector
2. Check:
Lead
Coupler
Connector
Moisture → Dry with an air blower.
Rust/stains → Connect and disconnect several
times.
3. Check:
All co ...
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 ...