Yamaha YZF-R125 Service Manual: Cylinder head

Installing the exhaust assembly

1. Install: Exhaust assembly "1" Exhaust pipe nuts "2" Exhaust assembly bolts "3" "4" NOTE: Do not fully tighten the nuts and bolts. 2. Tighten: Exhaust pipe nuts "2" Exhaust assem ...

Removing the cylinder head

1. Align: "I" mark "a" on the generator rotor (with the stationary pointer "b" on the generator cover) a. Turn the crankshaft counterclockwise. b. When the piston is at TDC on the compre ...

Other materials:

Checking the switches
1. Clutch switch 2. Main switch 3. Front brake light switch 4. Sidestand switch 5. Rear brake light switch 6. Neutral switch 7. Turn signal switch 8. Horn switch 9. Dimmer switch 10.Pass switch 11.Engine stop switch 12.Start switch Check each switch for continuity with the pocket tes ...

Starting failures
Engine 1. Cylinder and cylinder head - Loose spark plug - Loose cylinder head or cylinder - Damaged cylinder head gasket - Damaged cylinder gasket - Worn or damaged cylinder - Incorrect valve clearance - Improperly sealed valve - Incorrect valve-to-valve-seat contact - Incorrect valve timi ...

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 ...