Brake maintenance
Photos and  text  for checking the rear light brake and front brake pads and rear brake shoes are from the book(Owner's manual Yamaha XV750G)
Photo 1  Photo 2
1) Wear indicator 

A) Wear limit (0.031 in) 

 1) Wear limit

2) Wear indicator
Photo 3  Photo 4
1) Main body.

2)  Adjusting nut

 1)Level window (Lower level)
Photos and  text  for checking the rear light brake and front brake pads and rear brake shoes are from the book(Owner's manual Yamaha XV750G)

Brake light switch adjustment.

The brake light switch is operated by movement of the brake pedal. To adjust, hold the main body (photo3 #1) of the switch so it does not rotate and turn the adjusting nut (photo3#2). Proper adjustement is achieved when the brake light comes on just before the brake begins to take effect.

Checking the front brake pads and rear brakes shoes.

A wear indicator is provided on each brake(photo 1 & 2). This indicator allows checking of brake pads/shoes wear without disassembling the brake.
Front: Apply the brake and inspect the wear indicator(ph.1). If the brake pads are worn to the wear limit, have a Yamaha dealer or other qualified mechanic to replace the pads.
Rear : apply the brake and inspect the wear indicator(ph.2). If the indicator is reaches the wear limit line, ask a Yamaha dealer or other qualified mechanic to replace the shoes. This indicator is locate on the rear wheel (right side of the bike)

Inspecting the brake fluid level.

Insufficient brake fluid may let air enter the brake system, possibly causing the brakes to become ineffective. Before riding, check that the brake fluid is above the lower level (ph.4)and replenish when necessary. Observe these precautions:
1) When checking the fluid level, make sure the top of the master cylinder is level by turning the handlebars.
2) Use only the designated quality brake fluid. Otherwise, the rubber seals may deteriorate, causing leakage and poor brake
     performance. (Recommand brake fluid ; DOT #4) (NOTE : If DOT #4 is not available, #3 can be used)
3) Refill with the same type of brake fluid. Mixing fluids may result in a harmful chemical reaction and lead to poor brake
     performance.
4) Be careful that water does not enter the master cylinder (ph.4) when refilling. Water will significantly lower the boiling point
    of the fluid and may result in vapor lock.
5) Brake fluid may deteriorate painted surfaces or plastic parts. Always clean up spilled fluid immediately.
6) Have a Yamaha dealer or other qualified mechanic check the cause if the brake fluid level goes down.
 

Brake fluid replacement.

1) Complete fluid replacement should be done only by trained Yamaha service personnel or other qualified mechanics.
2) Have a Yamaha dealer or other qualified mechanic replace the following components during periodic maintenance or when
    they are damaged or leaking.
   A) Replace all rubber seals every two years.
   B) Replace all hoses every four years.

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