Bleeding the Brakes on a 2018 Kawasaki Ninja 400 ABS
Shop parts for a 2018 Kawasaki EX400 - Ninja 400 ABS Motorcycle.The 2018 Kawasaki EX400 – Ninja 400 ABS uses hydraulic disc brakes at both ends and is equipped with ABS. That means routine brake bleeding is handled through the caliper bleeder valves, just as on a conventional hydraulic system, while the ABS unit adds one important caveat: if air has entered the ABS hardware itself, a normal caliper bleed may not be enough. This guide walks you through refreshing the fluid and removing air from the front and rear circuits on the Ninja 400 ABS, with clear checks so you know when the job is complete and when it should go to a shop.
When the Ninja 400 ABS Needs a Brake Bleed
Bleeding is due when the front lever or rear pedal feels spongy, when the lever pulls closer to the grip than it used to, or when the fluid in either reservoir looks dark, cloudy, or contaminated. It is also necessary after any work that opened the hydraulic system, such as installing new brake lines, servicing a caliper, or replacing master cylinder components. Even without symptoms, brake fluid absorbs moisture over time, which lowers its boiling point and can contribute to brake fade during hard or repeated use. Many riders refresh brake fluid on a regular schedule for that reason alone.
Tools and Supplies to Have Ready
- Fresh brake fluid of the type marked on the master cylinder reservoir cap, from a sealed container
- A box-end wrench that fits the bleeder valve
- Clear tubing that fits snugly over the bleeder valve
- A catch bottle for used fluid
- Rags or shop towels
- A syringe or turkey baster for removing old fluid from the reservoir
- A screwdriver or driver that fits the reservoir cap screws
- Optional: a one-way check-valve bleeder or vacuum bleeder to make one-person bleeding easier
Prepare the Bike and Protect the Finish
Support the Ninja 400 ABS securely upright on a stand so it cannot tip while you are working the lever and pedal. Turn the handlebars so the front reservoir sits level before you open it. Cover painted surfaces, plastics, and the instrument area with rags, because most brake fluids damage paint and plastic on contact. If fluid spills, wipe it up immediately and rinse the area with water. Keep the reservoir cap and diaphragm clean and set them where they will not pick up grit.
The Step-by-Step Bleeding Procedure
- Open the front reservoir and remove most of the old fluid with a syringe or turkey baster. Do not let the reservoir run dry; leave enough fluid to keep air from entering the master cylinder.
- Refill the reservoir with fresh fluid from the sealed container, leaving room for the diaphragm and cap to be reinstalled later.
- Attach the clear tubing to a front caliper bleeder valve and route the other end into the catch bottle. Fit the box-end wrench onto the bleeder.
- Squeeze the front lever several times, then hold it firmly against the grip.
- Open the bleeder about a quarter turn and watch fluid and air move through the clear tube. Close the bleeder before releasing the lever.
- Release the lever slowly, then repeat the squeeze-hold-open-close sequence. Check the reservoir often and top it off so it never draws air.
- Continue until fresh, clean fluid with no bubbles comes through the tube. If your bike has more than one front caliper, bleed each one in turn; as a general practice, start with the caliper farthest from the master cylinder.
- Move to the rear brake. Check the rear reservoir, remove old fluid if needed, and top it with fresh fluid. Attach the clear tube to the rear caliper bleeder and route it to the catch bottle.
- Press and hold the rear pedal, open the bleeder about a quarter turn, then close it before releasing the pedal. Repeat until the fluid runs clean and bubble-free, keeping the rear reservoir topped off throughout.
- When both circuits are done, tighten each bleeder snugly without overtightening. Fill each reservoir to the correct level marking, reinstall the diaphragm and cap, and clean any spilled fluid.
Finishing Checks and a Low-Speed Test
Inspect the bleeder valves and the banjo fittings at the master cylinders and calipers for leaks. The front lever and rear pedal should feel firm and consistent, not spongy, and they should not slowly sink under steady pressure. Spin each wheel by hand to confirm the brakes are not dragging. Before riding normally, test the brakes at low speed in a safe area and confirm they engage smoothly and release completely.
Troubleshooting and When to Visit a Shop
If the lever or pedal will not firm up after several bleeding attempts, if it firms only after pumping, if bubbles keep appearing, or if fluid is leaking from the master cylinder or caliper, stop and diagnose the problem rather than continuing to ride. Because this is an ABS-equipped Ninja 400, air that has entered the ABS unit itself—for example, after the reservoir ran dry or after ABS lines or components were disconnected—may require a dealer-level procedure or diagnostic tool. In that situation, or if you are not confident the system is free of air, have the bike inspected by a qualified shop before riding.
Related Shopping Categories
Shop Brake Fluid for a 2018 Kawasaki EX400 - Ninja 400 ABS Motorcycle.
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Shop Stands for a 2018 Kawasaki EX400 - Ninja 400 ABS Motorcycle.
Shop Brake Tools for a 2018 Kawasaki EX400 - Ninja 400 ABS Motorcycle.
Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.
