Yamaha YZF-R125 Service Manual: Air induction system
1. Air induction system hose (air filter case to reed valve assembly) 2. Air induction system reed valve assembly
3. Air induction system hose (reed valve assembly to exhaust pipe)
Checking the air induction system
Air injection
The air induction system burns unburned exhaust gases by injecting fresh air (secondary air) into the exhaust port, reducing the emission of hydrocarbons. When there is negative pressure at the exhaust port, the reed valve opens, allowing secondary air to flow into the exhaust port.
The required temperature for burning the unburned exhaust gases is approximately 600 to 700 C (1112 to 1292 F).
1. Check:
- Hoses
Loose connections
Connect
properly.Cracks/damage
Replace. - Cracks/damage
Replace.
2. Check:
- Air induction system reed valve assembly operation
a. Blow air into the pipe "1" of the air induction system reed valve assembly and check that it comes out from the pipe "2".
b. Blow air into the pipe "2" of the air induction system reed valve assembly and check that it does not come out from the pipe "1".
c. If faulty, replace the air induction system reed valve assembly.
Installing the throttle body
1. Install:
Throttle body joint clamps
NOTE:
Align the projections "a" on the throttle body joint
with the slot "b" in each throttle body joint clamp.
2. Install:
Throttle body joint ...
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 ...
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur during
operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting charts
repre ...
Checking the bulbs and bulb sockets
NOTE:
Do not check any of the lights that use LEDs.
Check each bulb and bulb socket for damage or
wear, proper connections, and also for continuity
between the terminals.
Damage/wear Repair or replace
the bulb,
bulb socket or both.
Improperly connected Properly
connect.
No c ...