Yamaha YZF-R125 Service Manual: Checking the fuel pressure
1. Check:
- Pressure regulator operation
a. Remove the fuel hose connector cover "1" and disconnect the fuel hose "2" from the fuel pump.
| CAUTION: Although the fuel has been removed from the fuel tank, be careful when removing the fuel hose, since there may be fuel remaining in it. |
NOTE:
Before removing the hose, place a few rags in the area under where it will be removed.
b. Connect the pressure gauge "3" and fuel
pressure adapter "4".
c. Start the engine.
d. Measure the fuel pressure. 
Faulty Replace the fuel tank (with fuel pump).
e. Connect the fuel hose and install the fuel hose connector cover.
Refer to "INSTALLING THE FUEL HOSE" on page 7-2.
Installing the fuel hose
1. Install:
Fuel hose
Fuel hose connector cover
CAUTION:When installing the fuel hose, make sure
that
it is securely connected, and that the fuel
hose connector cover is in t ...
Throttle body
...
Other materials:
Introduction
WARNINGDisc brake components rarely require
disassembly.
Therefore, always follow these preventive
measures:
Never disassemble brake components unless
absolutely necessary.
If any connection on the hydraulic brake
system is disconnected, the entire brake
sy ...
Checking the rectifier/regulator
1. Check:
Rectifier/regulator output voltage
Out of specification → Replace the
rectifier/
regulator.
a. Set the engine tachometer to the spark plug
lead.
b. Connect the pocket tester (DC 20 V) to the
rectifier/regulator coupler as shown.
Positive tester probe
red "1"
Negat ...
Handlebar switches
Left
Left
1. Pass switch "PASS"
2. Dimmer switch "/"
3. Turn signal switch "/"
4. Horn switch""
Right
Right
Engine stop switch "/"
Start switch""
Pass switch "PASS"
Press this switch to flash the headlight.
Dimmer switch "/"
Set this switch to""
for the high
beam an ...