Yamaha YZF-R125 Service Manual: Checking the radiator
1. Check:
Radiator fins
obstruction 
clean.
Apply compressed air to the rear of the radiator.
Damage
repair or replace.
NOTE:
Straighten any flattened fins with a thin, flat-head screwdriver.
2. Check:
- Radiator hoses
Cracks/damage
Replace.
3. Measure:
- Radiator cap opening pressure
Below the specified pressure
Replace the radiator cap.
a. Install the radiator cap tester "1" and radiator
cap tester adapter "2" to the radiator cap "3".
b. Apply the specified pressure for ten seconds and make sure there is no drop in pressure.
4. Check:
- Radiator fan
Damage
Replace.
Malfunction
Check and repair.Refer to "COOLING SYSTEM" on page 8-25.
Radiator
...
Installing the radiator
1. Fill:
Cooling system
(with the specified amount of the recommended
coolant)
Refer to "CHANGING THE COOLANT" on
page 3-15.
2. Check:
Cooling system
Leaks Repair or replace any
...
Other materials:
Checking the connections
Check the leads, couplers, and connectors for
stains, rust, moisture, etc.
1. Disconnect:
Lead
Coupler
Connector
2. Check:
Lead
Coupler
Connector
Moisture → Dry with an air blower.
Rust/stains → Connect and disconnect several
times.
3. Check:
All co ...
Removing the fuel tank
1. Extract the fuel in the fuel tank through the
fuel tank filler hole with a pump.
2. Remove:
Fuel hose connector cover "1"
3. Disconnect:
Fuel hose "2"
CAUTION:
Be sure to disconnect the fuel hose by
hand. Do not forcefully disconnect the
hose with tools.
A ...
Adjusting the exhaust gas volume
NOTE:
Be sure to set the CO density level to standard,
and then adjust the exhaust gas volume.
1. Remove:
Rider seat
Refer to "GENERAL CHASSIS" on page 4-1.
2. Set the main switch to "OFF".
3. Disconnect:
Self-diagnosis signal connector "1"
4. Connect:
FI diagnostic tool "2 ...