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:
Throttle position sensor
1. Check:
Throttle position sensor
a. Connect the digital circuit tester to the terminals
of the throttle body sensor assembly
coupler as shown.
Positive tester probe →
gray/red terminal "1"
Negative tester probe →
gray/black terminal "2"
b. Measure the throttle pos ...
Faulty lighting or signaling system
Headlight does not come on
- Wrong headlight bulb
- Too many electrical accessories
- Hard charging
- Incorrect connection
- Improperly grounded circuit
- Poor contacts (main or light switch)
- Burnt-out headlight bulb
Headlight bulb burnt out
- Wrong headlight bulb
- Faulty battery
- Fau ...
Removing the valves
The following procedure applies to all of the
valves and related components.
NOTE:
Before removing the internal parts of the cylinder
head (e.g., valves, valve springs, valve seats),
make sure the valves properly seal.
1. Check:
Valve sealing
Leakage at the valve seat Check
the valve
...