Yamaha YZF-R125 Service Manual: Circuit diagram

Charging system

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Troubleshooting

The battery is not being charged. NOTE: Before troubleshooting, remove the following part(s): 1. Rider seat 2. Left side panel 3. Left lower side cowling ...

Other materials:

Checking the rear brake hose
1. Check: Brake hoses "1" Cracks/damage/wear  Replace. 2. Check: Brake hose holder "2" Loose connection Tighten the holder bolt. Loose or open holder Fasten properly. 3. Hold the vehicle upright and apply the rear brake several times. 4. Check: Brake ho ...

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 2. Check: Cylinder head Damage/scratches   Replace. Cylinder head water jacket Min ...

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 timing chain tensioner rod, wind it clockwise with a thin screwdriver "1" until it stops. b. ...