Yamaha YZF-R125 Service Manual: Checking the camshaft sprocket and timing chain guide

Yamaha YZF-R125 Service Manual / Engine / Cylinder head / Checking the camshaft sprocket and timing chain guide

1. Check:

  • Camshaft sprocket More than 1/4 tooth wear "a" Replace
    the camshaft sprocket, timing chain and crankshaft as a set.

Checking the camshaft sprocket and timing chain guide


a. 1/4 tooth

b. Correct

1. Timing chain roller

2. Camshaft sprocket

2. Check:

Timing chain guide (exhaust side) Damage/wear Replace.


    Checking the cylinder head
    1. Eliminate: Combustion chamber carbon deposits (with a rounded scraper) NOTE: Do not use a sharp instrument to avoid damaging or scratching: Spark plug bore threads Valve seats ...

    Checking the timing chain tensioner
    1. Check: Timing chain tensioner Cracks/damage/rough movement Replace. a. Lightly press the timing chain tensioner rod into the timing chain tensioner housing by hand. NOTE: While pressing the ...

    Other materials:

    Checking the clutch housing
    1. Check: Clutch housing dogs "1" Damage/pitting/wear  Deburr the clutch housing dogs or replace the clutch housing. NOTE: Pitting on the clutch housing dogs will cause erratic clutch operation. 2. Check: Bearing Damage/wear Replace the bearing and clutch housin ...

    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. ...

    Replacing an auxiliary light bulb
    This model is equipped with two auxiliary lights. If an auxiliary light bulb burns out, replace it as follows. Remove the socket (together with the bulb) by pulling it out. Auxiliary light bulb Remove the burnt out bulb by pulling it out. Insert a new bulb into t ...

    2023 Copyright www.yam-r125.net |