2020 Kawasaki KLX140 Brake Fluid Replacement - Page 2

Road and Trail Guide

This is a step-by-step guide to replacing the brake fluid on a Kawasaki KLX140. It is based on the author’s observations and experience replacing the brake fluid on a 2020 Kawasaki KLX140L (and on many other motorcycles) and on information contained in the official Kawasaki KLX140 service manual, 2020 (part no. 99924-1390-14).

Read all of the instructions before beginning. It may be helpful to take photos prior to removing or repositioning parts to aid you later.

Use the correct tools for the job, and take your time.

Parts and supplies you may need

• fresh brake fluid from a sealed container, DOT3 or DOT4
• shop towels, rags

Tools you need or may find helpful

• torque wrench accurate at 7.8 N.m
• possible 3/8-inch to 1/4-inch adapter
• 1/4-inch drive ratchet, 8 mm socket
• 8 mm box-end wrench
• #2 Philips or JIS screw driver
• brake bleeder tool or a section of clear tubing and a container to catch brake fluid
• a syringe to remove brake fluid from brake fluid reservoir / master cylinder (or use brake bleeder tool)

The clear tubing needs to fit tightly on the brake bleeder valve. The tubing that I use has an inside diameter of about 5 mm (3/16 in). You'll need about 60 cm (2 feet), but you might want a bit more. You can get tubing at a hardware or building supply store.

The same basic procedures apply to both front and rear brakes except for the front brake, you'll be squeezing the front brake lever, and for the rear brake, you'll pushing down on the brake pedal.

You may need a helper, especially for the front brake.

• Remove the right side cover for easier access to the rear brake master cylinder.
• Level the brake fluid reservoir (master cylinder). You may achieve this by turning the handlebars (front) or by holding the bike vertical (rear) with a stand or a helper.
• Clean the outside of the brake reservoirs (master cylinders) and the area around them as well as the area around the brake bleeders on the calipers. Also, clean areas above the rear reservoir / master cylinder, so that dirt cannot fall into the opened reservoir.
• Cover the fuel tank and area around the master cylinder with rags to protect against spilled brake fluid. Wipe up any spills immediately.
• Remove the rubber cap on the brake caliper bleed screw, and then loosen the brake bleeder valve/screw with an 8 mm socket and ratchet, but leave the valve closed (snug) for now.
• Remove the reservoir cap and the rubber diaphragm by removing the cap screws. Wipe away any brake fluid dribbles.
• With a syringe, suck-up as much brake fluid from the reservoir as you can, and then fill up the reservoir with fresh brake fluid.
• Attach a clear plastic hose to the bleed screw, and insert the other end of the hose into a suitable container (a glass jar works).
• Repeat the following 4 steps until fresh brake fluid comes out of the plastic hose. Add fresh brake fluid to the reservoir and do not let the level get too low (or you will pump air into the system).
• 1. Apply the brake and hold it (keep squeezing it).
• 2. Open the bleed valve with an 8 mm box-end wrench.
• 3. Close the bleed valve.
• 4. Release the brake lever (pedal).
• Note: check the brake fluid level frequently and add fluid as needed. Don't let the brake fluid level drop to the bottom of the reservoir because air will be pumped into the brake line, and we don't want that.
• Bleed the brake (see below) if bubbles are noted after replacing the brake fluid or if the brake feels spongy. I routinely bleed the brakes as part of replacing the brake fluid.
• Remove the clear plastic hose.
• Tighten the bleed valve to 7.8 N.m (69 in-lb), and install the rubber cap.
• Top-up the brake fluid if low (look for an upper-level mark), but do not overfill. There needs to be room to install the reservoir diaphragm.
• Install the reservoir diaphragm and cap.
• With a damp cloth, wipe up any brake fluid dribbles.
• After changing the brake fluid, check the brake operation. If necessary, bleed the brakes.
• Check for leaks.

• Remove the reservoir cap (clean area first), and ensure that there is plenty of brake fluid. Add fluid as needed.
• With the reservoir cap off, slowly pump the brake lever several times until no air bubbles can be seen rising up through the fluid from the holes in the bottom of the reservoir.
• Attach as clear plastic hose to the bleed valve on the caliper (clean first) and place the other end into a container.
• Repeat the following 3 steps until no more air can been seen coming out of the hose.
• 1. Pump the brake lever until it becomes hard, apply the brake and hold it.
• 2. Quickly open and close the brake bleeder valve while applying pressure on the brake lever.
• 3. Release the brake lever.
• Notes: Do not let the brake fluid get too low. Tap the brake line from the caliper to the reservoir for easier bleeding.
• Remove the clear plastic hose.
• Tighten the bleed valve to 7.8 N.m (69 in-lb), and install the rubber cap.
• Check the brake fluid level. Add fluid if needed, but do not overfill. Install the reservoir diaphragm and cap.
• Check brake operation. Check for leaks.