Yamaha YZF-R125 Service Manual: Installing the piston and cylinder

Yamaha YZF-R125 Service Manual / Engine / Cylinder and piston / Installing the piston and cylinder

1. Install:

  • Top ring "1"
  • 2nd ring "2"
  • Oil ring expander "3"
  • Lower oil ring rail "4"
  • Upper oil ring rail "5"

NOTE:

Be sure to install the piston rings so that the manufacturer marks or numbers face up.

Installing the piston and cylinder


2. Install:

  • Piston "1"
  • Piston pin "2"
  • Piston pin clips "3"

NOTE:

  • Apply engine oil to the piston pin.
  • Make sure the arrow mark "a" on the piston points towards the exhaust side of the cylinder.
  • Before installing the piston pin clips, cover the crankcase opening with a clean rag to prevent the clips from falling into the crankcase.

Installing the piston and cylinder


3. Lubricate:

  • Piston
  • Piston rings
  • Cylinder (with the recommended lubricant)

4. Offset:

  • Piston ring end gaps

a. Top ring

b. Upper oil ring rail

c. Oil ring expander

d. Lower oil ring rail

e. 2nd ring

f. 20 mm (0.79 in)

A. Intake side

5. Install:

  • Dowel pins
  • Cylinder head gasket

  • Cylinder "1"

NOTE:

  • While compressing the piston rings with one hand, install the cylinder with the other hand.
  • Pass the timing chain and timing chain guide (intake side) through the timing chain cavity.

Installing the piston and cylinder


    Checking the piston pin
    1. Check: Piston pin Blue discoloration/grooves  Replace the piston pin and then check the lubrication system. 2. Measure: Piston pin outside diameter "a" Out of specification ...

    Generator and starter clutch
    ...

    Other materials:

    Checking the fuel sender
    1. Drain the fuel from the fuel tank. 2. Check: Fuel sender resistance Out of specification → Replace the fuel sender. a. Connect the pocket tester ( × 10) to the fuel sender coupler as shown. Positive tester probe sky blue "1" Negative tester probe orange/white " ...

    Chassis tightening torques
    NOTE: First, tighten the lower ring nut to approximately 48 Nm (4.8 m.kg, 35 ft.lb) with a torque wrench, then loosen the lower ring nut completely. Retighten the lower ring nut to 13 Nm (1.3 m.kg, 9.4 ft.lb) with a torque wrench. ...

    Removing the front wheel (disc)
    1. Stand the vehicle on a level surface. WARNINGSecurely support the vehicle so that there is no danger of it falling over. 2. Elevate: Front wheel NOTE: Place the vehicle on a suitable stand so that the front wheel is elevated. 3. Remove: Front brake caliper NO ...

    2024 Copyright www.yam-r125.net |