Yamaha YZF-R125 Service Manual: Checking the cylinder head breather hose
1. Remove:
- Left side panel Refer to "GENERAL CHASSIS" on page 4-1.
2. Check:
- Cylinder head breather hose "1"
Cracks/damage → Replace.
Loose connection → Connect properly.
| CAUTION: Make sure the cylinder head breather hose is routed correctly. |
3. Install:
- Left side panel Refer to "GENERAL CHASSIS" on page 4-1.
Checking the fuel line
1. Remove:
Left side panel
Refer to "GENERAL CHASSIS" on page 4-1.
2. Lift the fuel tank. (Do not disconnect the fuel
hose, drain hose
3. Check:
Fuel hose "1"
Cracks/damage → Replac ...
Checking the exhaust system
1. Check:
Exhaust assembly "1"
Cracks/damage → Replace.
Exhaust pipe gasket "2"
Exhaust gas leaks → Replace.
2. Check:
Tightening torques of the exhaust pipe nuts
"3" an ...
Other materials:
Removing the cylinder head
1. Align:
"I" mark "a" on the generator rotor
(with the stationary pointer "b" on the generator
cover)
a. Turn the crankshaft counterclockwise.
b. When the piston is at TDC on the compression
stroke, align the "I" mark "c" on the camshaft
sprocket with the mark "d" on the
cylinder h ...
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. ...
Faulty clutch
Clutch slips
1. Clutch
Improperly assembled clutch
Improperly adjusted clutch cable
Loose or fatigued clutch spring
Worn friction plate
Worn clutch plate
2. Engine oil
Incorrect oil level
Incorrect oil viscosity (low)
Deteriorated oil
Clutch drags
1. Clutch
Unevenly t ...