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:
Overheating
Engine
1. Clogged coolant passages
Cylinder head and piston
Heavy carbon buildup
2. Engine oil
Incorrect oil level
Incorrect oil viscosity
Inferior oil quality
Cooling system
1. Coolant
Low coolant level
2. Radiator
Damaged or leaking radiator
Faulty radiator cap
...
Incorrect engine idling speed
Engine
1. Cylinder and cylinder head
Incorrect valve clearance
Damaged valve train components
2. Air filter
Clogged air filter element
Fuel system
1. Throttle body
Damaged or loose throttle body joint
Improperly adjusted engine idling speed (idle
adjusting screw)
Improper ...
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
To check the drive chain slack
Place the motorcycle on the sidestand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
Shift the transmission in ...