Yamaha YZF-R125 Service Manual: Gaskets, oil seals and o-rings
1. When overhauling the engine, replace all gaskets, seals and O-rings. All gasket surfaces, oil seal lips and O-rings must be cleaned.
2. During reassembly, properly oil all mating parts and bearings and lubricate the oil seal lips with grease.
- Oil
- Lip
- Spring
- Grease
Replacement parts
Use only genuine Yamaha parts for all replacements.
Use oil and grease recommended by
Yamaha for all lubrication jobs. Other brands
may be similar in function and appearance, but
inferior in qua ...
Lock washers/plates and cotter pins
After removal, replace all lock washers/plates
"1" and cotter pins. After the bolt or nut has been
tightened to specification, bend the lock tabs
along a flat of the bolt or nut.
...
Other materials:
Replacing the fuses
Replacing the fuses
Fuse box
Spare fuse
Headlight fuse
Signaling system fuse
Ignition fuse
Radiator fan fuse
Main fuse
The fuse box is located under the rider
seat.
If a fuse is blown, replace it as follows.
Turn the key to "OFF" and turn off
the electrical circuit i ...
Incorrect engine idling speed
Engine
1. Cylinder and cylinder head
Incorrect valve clearance
Damaged valve train components
2. Air filter
Clogged air filter element
Fuel system
1. Throttle body
Damaged or loose throttle body joint
Improperly adjusted engine idling speed (idle
adjusting screw)
Improper ...
Checking the speed sensor
1. Check:
Speed sensor output voltage
Out of specification → Replace.
a. Connect the pocket tester (DC 20 V) to the
speed sensor coupler (wire harness end) as
shown.
Positive tester probe
gray "1"
Negative tester probe
gray/black "2"
b. Set the main switch to "ON".
c. ...