The Kawasaki Vulcan's braking system is divided into two separate systems for front and rear brakes. The front brakes are a disc braking system which relies on hydraulic pressure. The brake fluid in this line is under significant pressure and over time and deteriorate and take on water, air may enter the system, or the fluid may cause the brakes to feel "spongy" and respond less accurately than when the fluid was fresh. Accordingly, changing the brake fluid is an essential part of periodic maintenance. The fluid should be changed at least every two years or anytime the rider notices a loss in brake responsiveness.
Brake fluid is cheap, so there's no excuse for not performing this on a regular basis.
To begin, you will need:
1. Fresh brake fluid (DOT 3 or 4, more on this later).
2. Socket and wrench set (specifically Metric 10mm socket, 8mm and 10mm wrench)
3. Phillips head screwdriver.
4. Manual for further information.
5. Not pictured, a "one man brake bleeder" which makes bleeding the brakes significantly easier if bleeding is necessary.
Step 1 - Turn your attention to the brake fluid reservoir on the top right handlebar.
Step 2 - Open the top of the reservoir with the phillips head screwdriver.
Step 3 - Turn your attention to the bleed valve on the right front disc brake mechanism.
Step 4 - Pop off the small rubber covering and attach a length of tubing, or preferably, a "one man brake bleeder" kit to the valve.
The "one man brake bleeder" operates as a secondary valve which allows fluid to leave the brake mechanism, but doesn't allow air to re-enter. By keeping the upper reservoir full with fresh fluid as the old fluid is drained, this ensures no air enters the system and makes traditional bleeding unecessary. These kits are available at Auto-Zone or NAPA for about $7, and are well worth it.
Step 5 - With the bleeder attached, make a 1/4 turn counterclockwise to loosen the bleeder valve. This will open the valve and allow the old fluid to drain.
Step 6 - Slowly pump the brake handle, this will expel the old fluid out the valve. Ensure that fresh fluid constantly keeps the upper reservoir full of fluid to prevent air from entering the system.