Bleeding the Brakes on a 2018 Honda NC750X
Shop parts for a 2018 Honda NC750X Motorcycle.
The 2018 Honda NC750X uses hydraulic disc brakes at both ends, and ABS was offered on this model. The front lever and rear pedal each push fluid through a sealed circuit to a caliper. When air enters that circuit or the fluid gets old, lever feel and stopping performance suffer. Bleeding pushes fresh fluid through the system and carries trapped air out with it. This guide walks through a caliper bleed for a DIY rider with basic hand tools. If your bike is ABS-equipped, the same caliper-level procedure applies for routine fluid refresh; the ABS unit only changes the plan if air has entered the modulator itself.
Why and When to Bleed the NC750X Brakes
A spongy lever, a pedal that feels soft, or a lever that pulls closer to the grip than it used to are the classic signs that air is in the system. Dark or cloudy fluid in the reservoir is another clue that the fluid is past its useful life. Bleeding is also necessary after any work that opened the hydraulic system, such as new brake lines, caliper service, or master cylinder work. Even without symptoms, brake fluid absorbs moisture over time. That moisture lowers the fluid's boiling point, which can lead to brake fade under hard or repeated use. Many riders refresh the fluid on a regular schedule for that reason alone.
Tools and Supplies for the Job
- 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 nipple
- A catch bottle for old 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
A one-way check-valve bleeder or a vacuum bleeder can make the job easier when you are working alone, but neither is required. The basic lever-and-bleeder method works fine if you follow the sequence carefully.
Preparation and Paint Protection
Support the bike securely upright on a stand so the reservoirs sit level. Turn the handlebars until the front reservoir is as flat as possible 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 a spill happens, wipe it up immediately and rinse the area with water. Keep the reservoir cap and diaphragm clean, and do not leave the reservoir open any longer than necessary.
Bleeding the Front and Rear Hydraulic Systems
The NC750X has separate hydraulic circuits for the front and rear brakes, so finish one before moving to the other. If your bike has more than one front caliper, treat each caliper as its own bleed point. As a general practice, start with the caliper farthest from the master cylinder when a single master cylinder feeds more than one caliper. On this bike, the front master cylinder is at the lever and the rear master cylinder is at the pedal.
- Clean the reservoir cap and surrounding area, then remove the cap and diaphragm. Do not let dirt or debris fall into the reservoir.
- Use the syringe or turkey baster to remove most of the old fluid from the reservoir. Leave a little fluid at the bottom so you do not push air into the system.
- Refill the reservoir with fresh fluid of the type marked on the cap. Keep the level near the full mark as you work.
- Fit the box-end wrench onto the bleeder valve. Push the clear tubing onto the bleeder nipple and route the other end into the catch bottle. The tubing should fit snugly.
- For the front brake, squeeze the lever slowly and hold it firm. For the rear brake, press the pedal and hold it. Do not pump rapidly.
- Open the bleeder about a quarter turn. Fluid and air will move into the tube. Watch for bubbles, then close the bleeder before the lever or pedal reaches the end of its travel or before you release it.
- Release the lever or pedal slowly. Check the reservoir level and top it off. Never let the reservoir run dry, or you will draw air back into the system.
- Repeat the squeeze-hold-open-close-release sequence until the tube shows clean fluid with no bubbles. Keep topping off the reservoir throughout.
- Move to the rear circuit if you have not done it yet. Use the pedal and the same sequence. Check the reservoir often.
- If your bike has more than one front caliper, bleed each one in turn and finish one before starting the next.
- When both circuits are done, close the bleeder snugly without overtightening. Fill the reservoir to the correct level marking.
- Reinstall the diaphragm and cap. Clean any spilled fluid with rags, and rinse painted or plastic surfaces with water if fluid touched them.
Finishing Checks and Leak Inspection
After the reservoir is closed, check the bleeder valves and the banjo fittings at the master cylinder and caliper for weeping. Wipe everything dry, then pump the lever and pedal a few times and look again. A small seep can turn into a serious problem, so do not ignore any sign of fluid at a fitting. Make sure the reservoir cap and diaphragm are seated correctly and that the fluid level is at the marking.
Test Before You Ride
The lever and pedal should feel firm and consistent, not spongy, and they should not slowly sink under steady pressure. Spin each wheel to confirm the brakes are not dragging. Test the brakes at low speed in a safe area before riding normally. If the lever still feels soft or the bike does not stop with authority, do not ride it. Recheck the reservoir level and repeat the bleed, or take the bike to a shop.
Troubleshooting and When to Stop
A lever that will not firm up after several bleeding attempts, a lever that firms up only after pumping, persistent air bubbles, or fluid leaking from the master cylinder or caliper are reasons to stop and diagnose the problem. If the reservoir ran dry, or if the ABS unit or its lines were disconnected, air may be trapped in the ABS modulator where a caliper bleed cannot reach it. That situation may require a dealer-level procedure or diagnostic tool, so it is best handled by a shop. Do not ride a bike with a brake system that will not hold a firm lever or pedal.
Related Shopping Categories
Shop Brake Fluid for a 2018 Honda NC750X Motorcycle.
Shop Brake Lines for a 2018 Honda NC750X Motorcycle.
Shop Brake Pads for a 2018 Honda NC750X Motorcycle.
Shop Stands for a 2018 Honda NC750X Motorcycle.
Shop Brake Tools for a 2018 Honda NC750X 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.
