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:
Multi-function display
1. Multi-function display
2. "RESET/SELECT" button
The multi-function display is equipped with the
following:
a speedometer (which shows the riding speed)
an odometer (which shows the total distance
traveled)
two tripmeters (which show the distance traveled
since they were last ...
Assembling the front brake caliper
WARNING
Before installation, all internal brake components
should be cleaned and lubricated
with clean or new brake fluid.
Never use solvents on internal brake components
as they will cause the brake caliper
dust seals and piston seals to swell and
distort.
...
Checking the camshaft
1. Check:
Camshaft lobes
Blue discoloration/pitting/scratches
Replace
the camshaft.
2. Measure:
Camshaft lobe dimensions "a" and "b"
Out of specification Replace
the camshaft.
3. Check:
Camshaft oil passage
Obstruction Blow out with
compressed air. ...