Bleeding the Brakes on Your 2019 Honda Monkey
Shop parts for a 2019 Honda Monkey Motorcycle.What You’re Working With on This Bike
The 2019 Monkey is a hydraulic-brake machine at both ends. Up front, a master cylinder on the right handlebar feeds a caliper at the wheel. Out back, a pedal-actuated master cylinder feeds its own rear caliper. That is a meaningful difference from the vintage Monkeys that relied on cable-operated drum brakes — on this bike, both circuits move fluid, so both can be bled and both benefit from a periodic flush. The front lever and the rear pedal work independently, with no linked or combined braking to complicate the sequence, so you can treat each circuit as a separate job and take them one at a time.
Depending on where it was sold, this bike may also carry ABS. The quickest way to know is to watch the instrument cluster at key-on: if an ABS indicator lights briefly and then extinguishes, the system is fitted. That detail matters for one reason. A routine bleed at the caliper bleeder is still the correct way to refresh fluid on an ABS-equipped bike, but if air has been pushed up into the ABS unit itself, the home procedure will not clear it.
When a Bleed Is Actually Due
Brake fluid is hygroscopic, meaning it absorbs moisture from the air over time. That absorbed water lowers the fluid’s boiling point, and under hard or repeated braking the fluid can boil and create vapor in the lines — which feels exactly like air and produces the same mushy lever. This is why many riders refresh the fluid on a set interval even when nothing feels wrong yet.
On top of the calendar, bleed the Monkey when the lever or pedal feels spongy, when the lever creeps closer to the grip than it used to, when the fluid in the reservoir looks dark or cloudy rather than clear, or after any work that opened the hydraulic system — new lines, caliper service, or master cylinder repairs. A lever that firms up only after two or three quick pumps is a classic sign that air is in the circuit.
Tools and Supplies to Have Ready Before You Start
- Fresh brake fluid of the type printed on your master cylinder reservoir cap, from a sealed container. Do not substitute a different type and do not use a bottle that has been open and sitting on a shelf.
- A box-end wrench that fits the bleeder valve snugly. A box-end grips the flats fully and is far less likely to round the bleeder than an open-end wrench.
- A length of clear tubing that fits tightly over the bleeder nipple, plus a small catch bottle.
- Rags or shop towels, and a syringe or turkey baster for pulling old fluid out of the reservoir.
- The correct driver for the reservoir cap screws.
- Optional but genuinely helpful for solo work: a one-way check-valve bleeder or a vacuum bleeder.
Setting Up Without Damaging the Bike
Get the Monkey supported securely upright on a stand so it cannot tip while you are leaning on the lever. Turn the handlebars until the front reservoir sits level, because an angled reservoir will spill fluid the moment the cap comes off. Then drape rags over the tank area, the plastics, the instrument cluster, and anything else below the reservoir. Brake fluid attacks paint and many plastics on contact, so wipe any drip immediately and rinse the area with water if a spill does happen. Keep the cap on the reservoir until you are genuinely ready to open it.
The Bleeding Procedure, Front Then Rear
- Remove the reservoir cap and diaphragm and set them somewhere clean, away from where they can pick up grit.
- Use the syringe or baster to draw most of the old fluid out of the reservoir. Do not pump the lever while the reservoir is nearly empty.
- Refill with fresh fluid and keep the bottle capped between pours.
- Slip the box-end wrench over the front bleeder and push the clear tubing onto the nipple, routing the other end into the catch bottle. A little fluid already in the bottle helps you see bubbles.
- Squeeze the front lever slowly and hold it steady.
- Open the bleeder about a quarter turn and watch fluid and air travel down the tube.
- Close the bleeder fully before you release the lever. Releasing with the bleeder open pulls air straight back into the caliper.
- Release the lever slowly, then repeat the squeeze-hold-open-close-release cycle. Check the reservoir level every few cycles and top it off — it must never run low enough to draw air in at the master cylinder.
- Keep going until the fluid coming through the tube is fresh, clean, and free of bubbles.
- With the lever held, close the bleeder snugly — firm enough to seal, not so hard that you damage the seat — then pull the tube off.
- Move to the rear caliper and repeat the same sequence using the pedal instead of the lever, pressing and holding the pedal where you would hold the lever.
- If your bike has more than one caliper on a circuit, bleed each one in turn rather than trying to do them together. General practice is to start with the caliper farthest from its master cylinder.
Finishing the Job Correctly
Top the reservoir to the level marking on the body of the master cylinder, not over it. Reinstall the diaphragm and cap and snug the screws down evenly. Wipe down the calipers, bleeders, and reservoir area with a damp rag to remove any fluid film, then look closely at the bleeder and at the banjo fittings for weeping. A bleeder that is seeping after you finish is a bleeder that will let air in later.
Testing Before You Ride
Pump the lever and the pedal a few times. Both should feel firm and consistent, and neither should slowly sink while you hold steady pressure on it. Spin each wheel by hand and confirm the brakes are not dragging — the wheel should turn freely with a light, even rub at most. Then ride the bike at walking pace in a safe, open area and apply each brake separately before you go anywhere at speed.
Troubleshooting and When to Hand It Off
If the lever will not firm up after several full bleeding cycles, if it only firms after pumping, or if you keep seeing bubbles no matter how much fluid you push through, stop and look for a source of air entry — a loose bleeder, a weeping banjo fitting, or fluid at the master cylinder. Leaks at the master cylinder or caliper are not something to ride on.
Two situations belong in a shop rather than a home garage. The first is any ABS-equipped bike where the reservoir ran dry or where the ABS unit or its lines were disconnected — air inside the ABS unit may need a dealer-level procedure or diagnostic tool to clear. The second is a brake system you simply cannot get a firm lever on after repeated attempts. Both are worth the tow.
Related Shopping Categories
Shop Brake Fluid for a 2019 Honda Monkey Motorcycle.
Shop Brake Lines for a 2019 Honda Monkey Motorcycle.
Shop Brake Pads for a 2019 Honda Monkey Motorcycle.
Shop Stands for a 2019 Honda Monkey Motorcycle.
Shop Brake Tools for a 2019 Honda Monkey 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.
