Yamaha YZF-R125 Service Manual: Gaskets, oil seals and o-rings

1. When overhauling the engine, replace all gaskets, seals and O-rings. All gasket surfaces, oil seal lips and O-rings must be cleaned.

2. During reassembly, properly oil all mating parts and bearings and lubricate the oil seal lips with grease.

Gaskets, oil seals and o-rings


  1. Oil
  2. Lip
  3. Spring
  4. Grease
    Replacement parts
    Use only genuine Yamaha parts for all replacements. Use oil and grease recommended by Yamaha for all lubrication jobs. Other brands may be similar in function and appearance, but inferior in qua ...

    Lock washers/plates and cotter pins
    After removal, replace all lock washers/plates "1" and cotter pins. After the bolt or nut has been tightened to specification, bend the lock tabs along a flat of the bolt or nut. ...

    Other materials:

    Checking the radiator fan motor
    1. Check: Radiator fan motor Faulty/rough movement → Replace. a. Disconnect the radiator fan motor coupler from the wire harness. b. Connect the battery (DC 12 V) as shown. Positive tester probe → blue "1" Negative tester probe → black "2" c. Measure ...

    Clutch lever
    Clutch lever Clutch lever The clutch lever is located at the left handlebar grip. To disengage the clutch, pull the lever toward the handlebar grip. To engage the clutch, release the lever. The lever should be pulled rapidly and released slowly for smooth clutch operation. Th ...

    Checking the primary driven gear
    1. Check: Primary driven gear "1" Damage/wear Replace the primary drive gear and clutch housing as a set. Excessive noise during operation  Replace the primary drive gear and clutch housing as a set. ...

    2026 Copyright www.yam-r125.net |