Bleeding the Brakes on a 2018 Ducati Scrambler Classic
Shop parts for a 2018 Ducati Scrambler Classic Motorcycle.
What This Job Covers on the Scrambler Classic
The 2018 Ducati Scrambler Classic uses hydraulic disc brakes at both ends, and it is equipped with ABS. The front brake is operated by the lever on the handlebar, while the rear brake is operated by the pedal. The front and rear circuits are separate, so you can service one end at a time. Because this bike has ABS, a normal bleed through the caliper bleeder is generally the right approach for routine fluid refresh and for removing air that entered at a caliper, line fitting, or master cylinder. If the reservoir ran dry, or if the ABS unit or its lines were disconnected, air may be trapped inside the ABS unit itself. That situation is beyond a typical home bleed and should go to a shop with the appropriate diagnostic equipment.
This guide is specifically about bleeding the hydraulic brakes—replacing old fluid and removing air. It is not a pad, rotor, caliper, or brake line replacement article. Those jobs can create the need for a bleed afterward, but the procedure below stays focused on the hydraulic system.
When Bleeding Is Needed
A spongy or soft front lever, a rear pedal that feels longer or less firm than usual, or a lever that pulls closer to the grip can all point to air in the system. Dark or cloudy fluid in the reservoir is another sign that the fluid is old and should be refreshed. Bleeding is also necessary after any work that opened the hydraulic system, such as installing new lines, servicing a caliper, or replacing or repairing a master cylinder.
Brake fluid absorbs moisture over time, which lowers its boiling point and can contribute to brake fade under hard or repeated use. That is why many riders refresh the fluid on a regular schedule even when the brakes still feel normal. If the lever slowly sinks while you hold steady pressure, treat that as a warning: there may be air in the system or a leak that needs attention before riding.
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
- A length of clear tubing that fits snugly over the bleeder valve
- A clean catch bottle for old fluid
- Rags or shop towels for spills and protection
- 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 the job easier for one person
Check the reservoir cap before you start and use only the fluid type printed there. Have all tools within reach before opening the reservoir so you are not searching for a wrench with the system open.
Preparation Before You Open the System
Support the Scrambler Classic securely upright on a stand. Turn the handlebars so the front reservoir sits as level 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.
With the bike upright, check that the rear reservoir is also in a workable position before opening it. Clean around the reservoir cap so dirt does not fall into the fluid. Remove the cap and diaphragm carefully, and keep them clean and nearby. Do not let old fluid drip onto the bike.
Step-by-Step Bleeding Procedure
- Remove most of the old fluid from the reservoir with a syringe or turkey baster. Leave enough to cover the bottom of the reservoir, but do not let it run dry.
- Refill the reservoir with fresh fluid from a sealed container, using the fluid type marked on the cap.
- Fit the clear tubing snugly over the bleeder valve on the caliper and route the other end into the catch bottle. Keep the bottle lower than the caliper, and put a small amount of fluid in it so you can see bubbles.
- For the front brake, squeeze the lever slowly and hold it firm. For the rear brake, press the pedal and hold it. Maintain pressure while you work the bleeder.
- Open the bleeder about a quarter turn with the box-end wrench. Fluid and air will exit through the tube. Watch the tubing for bubbles and color change.
- Close the bleeder before releasing the lever or pedal. Releasing with the bleeder open can draw air back into the system.
- Repeat the squeeze–hold–open–close–release sequence. Check the reservoir often and top it off with fresh fluid. Never let the level drop low enough to draw air into the master cylinder.
- Continue until fresh, clean, bubble-free fluid comes through the tube. Then close the bleeder snugly, but do not overtighten it.
- If a circuit has more than one caliper, bleed each caliper one at a time. As a general practice, start with the caliper farthest from its master cylinder.
- Repeat the same sequence for the rear brake using the pedal and the rear caliper bleeder, keeping the rear reservoir topped off throughout.
Finishing the Job Correctly
Once the fluid runs clean and bubble-free at each bleeder, tighten the bleeder snugly without overtightening. Fill the reservoir to the correct level marking, reinstall the diaphragm and cap, and clean any spilled fluid from the bike. Check for leaks at the bleeder and at the banjo fittings. Pump the lever and pedal a few times, then recheck the reservoir level and look again for weeping fluid.
Test Before You Ride
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 to confirm the brakes are not dragging. Test the brakes at low speed in a safe area before riding normally. If the lever or pedal does not feel right, do not ride the bike until the problem is resolved.
Troubleshooting and When to See a Shop
If the lever will not firm up after several bleeding attempts, if it firms up only after pumping, or if you keep seeing persistent air bubbles, stop and reassess. Fluid leaking from the master cylinder or caliper is another reason to stop. Any situation where air may have entered the ABS unit—such as a reservoir that ran dry or ABS lines that were disconnected—should go to a shop. A brake system that will not hold a firm lever is not safe to ride, so have the bike inspected before returning to the road.
Related Shopping Categories
Shop Brake Fluid for a 2018 Ducati Scrambler Classic Motorcycle.
Shop Brake Lines for a 2018 Ducati Scrambler Classic Motorcycle.
Shop Brake Pads for a 2018 Ducati Scrambler Classic Motorcycle.
Shop Stands for a 2018 Ducati Scrambler Classic Motorcycle.
Shop Brake Tools for a 2018 Ducati Scrambler Classic 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.
