Yamaha YZF-R125 Service Manual: Introduction

Yamaha YZF-R125 Service Manual / Chassis / Front brake / Introduction

WARNING

Disc brake components rarely require disassembly.

Therefore, always follow these preventive measures:

Never disassemble brake components unless absolutely necessary.
If any connection on the hydraulic brake system is disconnected, the entire brake system must be disassembled, drained, cleaned, properly filled, and bled after reassembly.
Never use solvents on internal brake components.
Use only clean or new brake fluid for cleaning brake components.
Brake fluid may damage painted surfaces and plastic parts. Therefore, always clean up any spilt brake fluid immediately.
Avoid brake fluid coming into contact with the eyes as it can cause serious injury.
FIRST AID FOR BRAKE FLUID ENTERING THE EYES:
Flush with water for 15 minutes and get immediate medical attention.

Checking the front brake disc

1. Remove: Front wheel Refer to "FRONT WHEEL" on page 4-6. 2. Check: Brake disc Damage/galling Replace. 3. Measure: Brake disc deflection Out of specification Correct the b ...

Other materials:

General maintenance and lubrication chart
TIP The air filter needs more frequent service if you are riding in unusually wet or dusty areas. Hydraulic brake service Regularly check and, if necessary, correct the brake fluid level. Every two years change the brake fluid. Replace the brake hoses every four ye ...

Checking the speed sensor
1. Check: Speed sensor output voltage Out of specification → Replace. a. Connect the pocket tester (DC 20 V) to the speed sensor coupler (wire harness end) as shown. Positive tester probe gray "1" Negative tester probe gray/black "2" b. Set the main switch to "ON". c. ...

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 undercut "a" Out of specification Scrape the mica to the proper measurement with a hacksaw blade ...