Yamaha YZF-R125 Service Manual: Electric starter

Installing the generator

1. Install: Woodruff key Generator rotor Washer Generator rotor nut NOTE: Clean the tapered portion of the crankshaft and the generator rotor hub. When installing the generator ro ...

Checking the starter motor

1. Check: Commutator Dirt Clean with 600 grit sandpaper. 2. Measure: Commutator diameter "a" Out of specification Replace the starter motor. 3. Measure: Mica under ...

Other materials:

Aftermarket Parts, Accessories, and Modifications
While you may find aftermarket products similar in design and quality to genuine Yamaha accessories, recognize that some aftermarket accessories or modifications are not suitable because of potential safety hazards to you or others. Installing aftermarket products or having other modif ...

Periodic maintenance and adjustment
Periodic inspection, adjustment, and lubrication will keep your vehicle in the safest and most efficient condition possible. Safety is an obligation of the vehicle owner/operator. The most important points of vehicle inspection, adjustment, and lubrication are explained on the followin ...

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 ...