Bleeding the Brakes on a 2023 Honda Monkey ABS
Shop parts for a 2023 Honda Monkey ABS Motorcycle.
The 2023 Honda Monkey ABS runs hydraulic disc brakes at both ends, and both circuits are monitored by an anti-lock braking system. The front brake is worked by the lever on the right handlebar and the rear by the pedal at the right footpeg, and each wheel has its own master cylinder, reservoir, and caliper. That independence is good news for a home mechanic: refreshing the fluid and purging air is the same basic job done twice, once at the front caliper and once at the rear. This guide walks you through both, along with the checks that tell you the job is finished properly.
Why and When a Monkey Needs a Bleed
Brake fluid is hygroscopic, meaning it pulls moisture out of the air over time. That absorbed water does two harmful things: it lowers the fluid’s boiling point, so hard or repeated braking can boil the fluid and produce a soft, fading lever, and it darkens the fluid as internals begin to corrode. On a small bike like the Monkey, where the brakes do a lot of work relative to the machine’s weight, a mushy lever is easy to notice and worth acting on early.
Bleed the system when the lever or pedal feels spongy, when the lever travels closer to the grip than it used to, when the fluid in either reservoir looks dark or cloudy, or after any work that opened the hydraulic circuit — new lines, caliper service, or master cylinder repairs. Many riders also flush the fluid on a regular interval as preventive maintenance, which is cheaper and far more convenient than discovering faded brakes mid-ride.
Tools and Supplies to Gather First
Have everything within arm’s reach before you open a reservoir, because once the cap is off you should not be walking away to hunt for a rag.
- Fresh brake fluid of the type printed on the master cylinder reservoir cap, from a sealed container — once a container has been opened, treat it as contaminated for future jobs
- A box-end wrench that fits the bleeder valve snugly
- Clear tubing sized to push firmly over the bleeder nipple
- A small catch bottle for the old fluid
- Rags or shop towels, plus a syringe or turkey baster for emptying the reservoir
- The correct driver for the reservoir cap screws
- Optional: a one-way check-valve bleeder or a vacuum bleeder, both of which make a solo job easier
Setting Up the Bike and Protecting the Finish
Put the Monkey on a stand so it sits upright and stable, and turn the handlebar until the front reservoir is level; a reservoir that is tilted will spill as soon as you remove the cap. Brake fluid attacks paint, plastic, and instrument lenses on contact, so drape rags over the tank area, the plastics around the bars, and the gauge cluster before you start. If a drop lands on a painted surface, wipe it immediately and rinse the area with water rather than scrubbing at it later.
Bleeding the Front Brake, Step by Step
Work slowly and keep the reservoir topped off at every stage. Drawing air into the system through a dry reservoir is the single most common way a simple bleed turns into a long afternoon.
- With the bike supported and the bars level, cover the surrounding surfaces with rags.
- Remove the reservoir cap and diaphragm, and set them down clean side up where dust cannot settle on them.
- Use the syringe or baster to draw most of the old fluid out of the reservoir. Leave a little at the bottom so you do not push air into the master cylinder.
- Refill with fresh fluid to the upper level marking.
- Slip the box-end wrench over the front caliper bleeder, then push the clear tubing onto the nipple and route the free end into the catch bottle.
- Squeeze the front lever firmly and hold it steady.
- Open the bleeder about a quarter turn. Fluid and air will push out through the tube; watch for bubbles.
- Close the bleeder before you release the lever. Releasing first pulls air back in past the threads.
- Release the lever slowly, then check the reservoir and top it off again.
- Repeat the squeeze, open, close, release cycle until the fluid arriving in the tube is clean and free of bubbles.
- As a general rule, start with the caliper farthest from the master cylinder. If your bike has two front calipers, treat each as its own bleed point and finish one completely before starting the other.
- Finish with the lever held, close the bleeder snugly, remove the tube, and top the reservoir to the correct level.
Bleeding the Rear Brake
The rear circuit on the Monkey is separate from the front, so it needs its own session at the rear caliper bleeder. The sequence is identical: empty most of the rear reservoir, refill with fresh fluid, fit the wrench and tube, then press and hold the pedal while you crack the bleeder, and close it again before releasing the pedal. Keep an eye on the rear reservoir level between cycles — it is smaller than the front and drops quickly.
Finishing Up and Checking for Leaks
Tighten the bleeder snugly by feel; it needs to seal, not to be crushed, and overtightening can damage the seat. Refill each reservoir to the level marking, reinstall the diaphragm and cap, and wipe away any fluid that escaped. Then inspect the bleeder valves and the banjo fittings at both the master cylinders and calipers for weeping, and pump the lever and pedal a few times to pressurize the system before you look again.
Testing Before You Ride
Both the lever and the pedal should feel firm and consistent, and neither should creep toward the end of its travel while you hold steady pressure. Spin each wheel by hand to confirm the brakes are not dragging. Then, in a safe open area, test the brakes at low speed before riding normally. Because this Monkey is ABS-equipped, a normal caliper bleed is fine for routine fluid service, but if the reservoir ever ran dry or the ABS unit or its lines were disconnected, air may be trapped where a home bleed cannot reach it — that job belongs to a dealer or a shop with the appropriate diagnostic tool.
When to Stop and Call a Shop
Take the bike in if the lever refuses to firm up after several honest attempts, if it firms only when you pump it, if bubbles keep appearing no matter how long you bleed, or if you find fluid weeping from a master cylinder or caliper. The same applies to any doubt about air inside the ABS unit. A professional diagnosis costs far less than a brake failure, and there is no shame in handing over a job that has stopped behaving predictably.
Related Shopping Categories
Shop Brake Fluid for a 2023 Honda Monkey ABS Motorcycle.
Shop Brake Lines for a 2023 Honda Monkey ABS Motorcycle.
Shop Brake Pads for a 2023 Honda Monkey ABS Motorcycle.
Shop Stands for a 2023 Honda Monkey ABS Motorcycle.
Shop Brake Tools for a 2023 Honda Monkey 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.
