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:

Checking the valve seats
The following procedure applies to all of the valves and valve seats. 1. Eliminate: Carbon deposits (from the valve face and valve seat) 2. Check: Valve seat Pitting/wear Replace the cylinder head. 3. Measure: Valve seat width C "a" Out of specification Replace the ...

Separating the crankcase
1. Remove: Crankcase bolts NOTE: Loosen each bolt 1/4 of a turn at a time, in stages and in the proper sequence as shown. A. Right crankcase B. Left crankcase 2. Turn: Shift drum segment NOTE: Turn the shift drum segment "1" to the position shown in the illustration. In this ...

Bleeding the hydraulic brake system
WARNINGBleed the hydraulic brake system whenever: the system is disassembled. a brake hose is loosened, disconnected or replaced. the brake fluid level is very low. brake operation is faulty. NOTE: Be careful not to spill any brake fluid or allow th ...