How to Change Motorcycle Brake Fluid (8 Steps)

Brake fluid stands as an indispensable component within the intricate network of a motorcycle’s braking system, where it fulfills a pivotal role in the seamless operation of this mechanical marvel. At its core, it is the medium through which the commanding force applied to the brake lever is meticulously conveyed to the brake caliper. Yet, its significance extends far beyond the mere transmission of power.

This unassuming hydraulic fluid operates as a guardian of the entire braking system, functioning as both a lubricant and a shield against the relentless forces of corrosion and the unforgiving specter of overheating. In essence, brake fluid is the unsung hero, ensuring that the motorcycle’s braking mechanism remains in optimal condition, guaranteeing not only its efficacy but, more importantly, the safety of the rider.

In the realm of motorcycle engineering, the performance of the braking system is not to be taken lightly. The trust and reliance placed on it during a thrilling dash down winding roads or a sudden emergency stop are immeasurable. It is, therefore, the brake fluid’s duty to offer unerring assurance in its role as the intermediary between the rider’s command and the brake caliper’s execution. With precision, it conveys the intent of the rider’s fingers on the brake lever into a seamless, instant response.

Beyond its vital role in power transmission, brake fluid operates as a sophisticated safeguard against the corrosive elements that would otherwise erode the system’s integrity over time. The constant exposure to moisture and environmental contaminants could spell disaster for any braking system. However, the judicious application of brake fluid forms a protective barrier, ensuring the longevity and resilience of the motorcycle’s brakes.

Furthermore, brake fluid acts as a cooling agent, actively mitigating the dangers of overheating. The braking process generates an immense amount of heat, and without the regulating influence of brake fluid, this heat could lead to the impairment of brake components and, ultimately, the loss of crucial stopping power. Thus, it is the role of brake fluid to maintain a stable and efficient braking system temperature, ensuring that the motorcycle rider can confidently rely on the brakes even during extended use.

In summary, the role of brake fluid in the world of motorcycle engineering cannot be overstated. It functions as the unsung hero, an essential cog in the wheel that guarantees not only the efficacy but, most importantly, the safety of the rider. As the invisible hand connecting the rider’s command to the brake caliper’s response, a guardian against corrosion, and a protector against the perils of overheating, brake fluid is the unyielding sentinel ensuring that every motorcycle journey remains both thrilling and secure.

In this comprehensive guide, we will delve into the essential process of changing your motorcycle’s brake fluid while addressing common questions that often arise when it comes to this crucial aspect of preventive maintenance.

The importance of proper brake fluid maintenance cannot be overstated, as it directly impacts your motorcycle’s safety and performance. To ensure that your bike’s braking system remains in optimal condition, follow these step-by-step instructions for changing your motorcycle brake fluid:

  1. Gather Your Equipment: Before embarking on this maintenance journey, it’s essential to have all the necessary equipment at hand. This includes brake fluid of the appropriate type, a wrench or socket set, a clean container to collect the old fluid, a turkey baster or a brake bleeder kit, and fresh rags.
  2. Locate the Brake Fluid Reservoir: The first step is to locate the brake fluid reservoir on your motorcycle. It is typically positioned near the handlebars, either on the handlebar itself or on the master cylinder assembly.
  3. Remove Old Brake Fluid: Carefully remove the old or used brake fluid from the reservoir. It’s crucial to dispose of the old fluid properly, as it can be harmful to the environment.
  4. Refill the Brake Fluid Reservoir: Now, fill the brake fluid reservoir with fresh, high-quality brake fluid. Be sure to use the type recommended by your motorcycle’s manufacturer, as using the wrong fluid can have adverse effects on your braking system.
  5. Bleed the Brakes: Bleeding the brakes is a critical step to remove air bubbles and ensure that the brake system functions correctly. You can do this with a friend’s assistance or by using a brake bleeder kit, depending on your preference and experience.
  6. Check Fluid Levels: After bleeding the brakes, double-check the brake fluid levels in the reservoir to ensure it is at the recommended level. Adjust as necessary.
  7. Tidy Up: Maintenance is not only about functionality but also aesthetics. Take some time to clean up any spilled brake fluid, ensuring your bike looks as good as it performs.
  8. Test Your Brakes: Before hitting the road, it’s imperative to test your brakes. Carefully engage the brakes while your motorcycle is stationary, ensuring they respond as expected. If there are any issues, further inspection or adjustments may be needed.

Many riders wonder about the cost associated with this maintenance task. A DIY brake fluid flush typically costs between $75 and $100, making it a cost-effective option for those with some mechanical aptitude. In contrast, outsourcing the job to a professional mechanic can set you back $100 or more, depending on labor rates and additional services.

Furthermore, for those seeking a more comprehensive brake system upgrade, replacing the fluid reservoir and bleeding the brake lines may push the expenses closer to the $400 mark. This investment can be worthwhile for riders looking to maximize their braking performance and safety.

In conclusion, if you’re keen to ensure the safety and longevity of your motorcycle while avoiding unnecessary repair expenses, it’s vital to familiarize yourself with routine maintenance tasks like changing your brake fluid. This relatively simple procedure can have a significant impact on your riding experience, making it a fundamental skill for any motorcycle enthusiast.

Motorcycle Brake Fluid Maintenance: Ensuring Optimal Safety and Performance

Your motorcycle’s braking system is a critical component that directly affects your safety and the overall handling of your two-wheeled machine. To maintain peak performance and rider safety, it’s imperative to understand how to change your motorcycle’s brake fluid effectively. In this comprehensive guide, we’ll provide step-by-step instructions on this essential maintenance task and offer valuable insights for riders of all experience levels.

Step 1: Gather Your Tools and Supplies

Before you embark on changing your brake fluid, ensure you have all the necessary equipment at your disposal. Here’s a list of items you’ll need:

  1. Brake Fluid: Acquire a fresh supply of DOT 3 or DOT 4 brake fluid, as recommended by your motorcycle manufacturer.
  2. Wrench: A wrench for the bleed valves on the brake caliper. The specific size depends on your motorcycle’s make and model, but generally, 7 mm, 8 mm, or 10 mm wrench sizes are used.
  3. Socket Set: If you don’t already have one, a socket set will come in handy.
  4. Spanner: You’ll need this for various adjustments.
  5. Hex-head Sockets: Ensure you have the appropriate sizes for your motorcycle.
  6. Screwdriver: Some motorcycles may require this for the brake fluid reservoir cover.
  7. Brake Bleeder Kit: A brake bleeder kit with a pressure monitoring gauge, like the Beley 2L 110V Universal Automatic Brake Bleeder Kit, is essential for removing air bubbles from the brake system.
  8. Vacuum Pump: Use a vacuum pump to purge the brake lines and calipers of old brake fluid effectively.
  9. Clear Tube: Have a clear tube that snugly fits the bleed nipple for bleeding the brakes.
  10. Brake Fluid Reservoir Funnel: This tool helps prevent spillage while topping up the brake fluid reservoir.
  11. Catch Pan: To collect old brake fluid while bleeding your brakes.
  12. Rag or Paper Towel: Keep these handy for cleaning up any fluid spills.
  13. Working Gloves: Protect your hands from contact with brake fluid, which can cause skin irritation due to its corrosive nature.
  14. Safety Glasses: Wear safety glasses to shield your eyes from brake fluid droplets, which can cause eye damage or irritation.
  15. Protective Cloth: Use a cloth to cover areas prone to spills, such as the bottom of the brake fluid reservoir.

Step 2: Locate Your Motorcycle’s Brake Fluid Reservoir

After gathering your tools, the next step is to locate your motorcycle’s brake fluid reservoir. The reservoir’s position may vary depending on your bike’s make and model. Generally, you can find it near the brake lever on the handlebars or close to the brake pedal. The brake fluid reservoir appears as a small container with a cap, typically made of plastic, metal, CNC aluminum alloy, acrylic, or glass. Consult your owner’s manual for precise location details.

Step 3: Remove Old Brake Fluid

Once you’ve located the brake fluid reservoir, use a wrench to open the cap. The size of the reservoir cap may vary based on your motorcycle’s make and model, with diameters typically ranging between 32 mm and 40 mm. Make sure to select an appropriately-sized wrench to open the cap.

Attach a hose to the bleeder valve of your bike using a brake bleeder kit and place the other end of the hose in a catch pan or container to collect the old hydraulic fluid. After opening the bleeder valve, pump the brake lever or pedal until all the old brake fluid is drained from your motorcycle.

Some riders opt for using a clean syringe or turkey baster to remove old brake fluid from their bikes. While these methods can be effective, a brake bleeder kit is generally considered the most efficient way to remove brake fluid.

After completely draining the old brake fluid, use a clean rag or paper towel to wipe away any debris or buildup around the reservoir opening.

Step 4: Refill the Brake Fluid Reservoir

At this stage, use a brake fluid funnel to top up the reservoir with fresh brake fluid. Before refilling, inspect the inside of the reservoir for any dirt or debris accumulation and clean it if necessary. Ensure that you’re using the correct type of brake fluid, following the manufacturer’s recommendations or your owner’s manual.

Fill the reservoir to the recommended level, taking care not to spill the fluid on sensitive components or your motorcycle’s paint finish. Overfilling the reservoir can lead to issues like brake fluid aeration, spongy brakes, reduced braking performance, fluid leaks, and an increased risk of brake failure. After filling the reservoir, securely close the cap and check for sufficient pressure in the brake system by squeezing the brake lever or pedal a few times.

(Tip: ABS-equipped motorcycles with pump systems may require priming after a brake fluid change to eliminate air and ensure proper function, preventing wheel lock-up during braking).

Step 5: Bleed the Brakes

To bleed the brake lines, locate the brake bleeder valve on the brake caliper, attach a bleeder hose, and open the valve. Pump the brake lever or pedal to allow old brake fluid or air bubbles to escape. Close the bleeder valve and release the brake pedal or lever. Repeat these steps until there are no more air bubbles in the bleeder hose, and your brake lever and pedal are responsive.

The quantity of brake fluid needed for bleeding a set of motorcycle brakes typically depends on the condition of the fluid in the reservoir. In most cases, 50 ml of brake fluid is sufficient. However, if the brake fluid is old or severely discolored, you may require more for a complete flush, bleed, and brake fluid refill.

The timing for bleeding your brakes depends on your driving habits and OEM recommendations. Generally, it’s recommended to bleed your brakes every two years, but as part of preventive maintenance, consider doing it annually. Regular bleeding helps ensure the proper function of your brake system and prevents the accumulation of air bubbles or contaminants in the brake fluid.

There are several signs that indicate it’s time to bleed your brakes:

  1. Once a year: Consider bleeding your brakes annually for preventive maintenance.
  2. Change in brake fluid color: If your brake fluid becomes darker, it’s a clear sign of moisture absorption, and bleeding is likely necessary.
  3. Soft or spongy brakes: Feeble or spongy brakes often indicate the presence of air in the brake lines. Bleeding is necessary to correct the pressure and remove trapped air.
  4. Longer-than-usual stopping distances: If your motorcycle’s braking distance increases, it may be due to fouled brake fluid or the need for bleeding.
  5. After finding a leak: Brake fluid leaks not only lead to fluid loss but also introduce air bubbles into the brake system, necessitating bleeding.
  6. When replacing worn brake pads or changing rotors: Changing these components can introduce air into the master cylinder, requiring bleeding.
  7. Following brake system repairs: Whenever you service or replace a brake system component, it’s essential to bleed the brake lines to ensure proper brake fluid quality and system reliability.
  8. Before a long ride: As a precaution, bleeding the brake lines before an extended journey reduces the risk of brake system problems on the road.

(Tip: Avoid letting the brake fluid reservoir run dry during bleeding, as this can require you to start the process over. Slowly pouring brake fluid into the reservoir is also recommended to prevent the introduction of air bubbles that can affect performance).

Step 6: Check Fluid Levels

After bleeding the brake system, check that the brake fluid level in the reservoir matches the OEM-recommended level. This step is crucial to ensure that your motorcycle’s braking system functions correctly and that the brake fluid level is optimal for safe operation. Maintaining the correct brake fluid level is essential because insufficient levels can lead to brake system malfunctions, while excessive levels can over-pressurize the system, negatively impacting performance.

Step 7: Tidy Up Your Workspace

With your brake system now in top shape and the brake fluid at the right level, it’s time to clean up your motorcycle and workspace. Ensure the reservoir cap and the diaphragm under it are clean. Check for any spilled brake fluid or splatters on the body paint and confirm that washers, sealers, and components are securely fitted to prevent leaks. Verify that all brake line connections, valves, and other parts of your motorcycle’s brake system are tight and secure. The same applies to the brake fluid reservoir cap.

Dispose of the used brake fluid, which was purged from your brake fluid reservoir, in a leak-proof container with a tight-fitting lid, following local regulations on hazardous waste disposal in your area.

Step 8: Test Your Brakes

After completing steps #1 to #6, it’s time to test the brakes on your motorcycle to ensure they are functioning properly. This testing should go beyond squeezing the brake lever or pedal and checking for pressure or sponginess. Perform the following checks:

  1. Start the engine and let your motorcycle warm up.
  2. Check the brake lever and pedal for feebleness or unresponsiveness.
  3. Test the brakes at low speeds by gently applying them. Observe if your motorcycle stops smoothly and evenly after the brakes are engaged.
  4. Test the brakes at higher speeds by applying them firmly. Ensure your motorcycle comes to a halt without skidding.
  5. Assess brake feel and performance while turning or cornering. Watch for any signs of losing control or uneven stopping.

If all these tests pass successfully, congratulations! You are now ready for your next two-wheeled adventure. If any issues persist, repeat step #5 until your brake system is completely free of air bubbles.

Signs of a Compromised Brake Fluid Reservoir

A compromised brake fluid reservoir can exhibit various symptoms, which include changes in the brake fluid’s color or physical damage to the reservoir itself. Keep an eye out for the following indicators:

  1. Visible Leaks: A compromised brake fluid reservoir may have visible leaks, leading to a consistently low fluid level.
  2. Brake Fluid Discoloration: Darkening of brake fluid can indicate contamination or buildup in the reservoir.
  3. Severe Contamination: Water or foreign substances can cause severe contamination, leading to a swollen or cracked brake fluid reservoir.

Recommended Brake Fluid Change Intervals

According to Bennetts, it’s advisable to replace motorcycle brake fluid every two years, regardless of usage severity. This is because brake fluids tend to absorb water over time, affecting their braking capabilities. Moisture can infiltrate the reservoir, causing tiny pockets of water that compromise brake performance.

In the realm of motorcycle ownership, the maintenance and care of your trusty thumper extend beyond the thrill of daily commutes or the sporadic weekend escapades down iconic routes like the legendary Route 66 or the scenic Pacific Coast Highway. Amidst the exhilaration of the open road, one often-overlooked yet critical aspect of motorcycle upkeep is the regular maintenance of your brake system, specifically, the brake fluid.

Now, let’s dive into the intricate world of motorcycle brake fluid and its ever-so-important changing intervals. The frequency of this maintenance chore hinges on a myriad of factors, chief among them being the intensity of your two-wheeled adventures, the capricious forces of Mother Nature, the age and composition of your brake fluid, the degree of contamination, and the recommendations of the motorcycle’s manufacturer.

For those who engage in relatively modest riding habits, where the hum of the engine primarily serves the daily commute and the occasional leisurely cruise, the recommended interval for changing your motorcycle brake fluid generally extends to a year or whenever you undertake a full-service checkup on your brake system or replace critical components. This timeframe provides a stable foundation for the safe and effective operation of your bike’s brakes, safeguarding your journeys on the asphalt.

But, let’s not get mired in the minutiae of DOT 3 and DOT 4 motorcycle brake fluids, for the difference in change intervals between them isn’t as monumental as one might imagine. Typically, for the former, a switch-up every 1 to 2 years is the norm, whereas the latter exhibits a tad more resilience, clocking in at up to two years before necessitating replacement. However, as with most things in the motorcycle world, these timelines aren’t set in stone. They oscillate in the delicate dance of riding frequency, the unpredictability of climate, the chemistry of brake fluid, the lurking presence of contaminants, and the sage advice dispensed by the manufacturer of your two-wheeled steed.

Now, let’s delve into a selection of the finest elixirs for your motorcycle’s braking system. These are the champions of hydraulic performance and corrosion resistance, poised to keep your braking game strong and consistent:

Lucas Oil 10825 DOT 3 Synthetic Brake Fluid: This top-tier brake fluid boasts a unique PEG ether blend with additives that conform to the stringent standards of FMVSS No. 116 and SAE J1703. Its compatibility extends to both disc and drum brakes and DOT 3 clutch systems. As a potent lubricant, it thwarts corrosion and safeguards seals. Remarkably, it plays well with other fluids and most rubber components in your brake system.

Maxima 40-03901 XL Chain Case/Gear Oil: In the realm of brake fluids, this high-quality offering stands as a guardian against wear and corrosion, custom-designed for the rigors of motorcycle chain cases and gearboxes, including V-Twin Sportster transmissions. It promises unwavering performance, extending the lifespan of your drivetrain with a synthetic blend that ensures seamless shifting and clutch engagement.

Motorex 109911 DOT 5.1 Brake Fluid: This high-performance synthetic brake fluid is a versatile marvel, suitable for all hydraulic brake systems. Its poly glycol-based formula aligns with DOT 5.1, DOT 4, and DOT 3 standards, excelling at corrosion protection and oxidation resistance. With an impressive boiling point, it delivers consistent and reliable braking performance, ensuring your safety and peace of mind on the road.

Motul 100949 RBF600 Racing Brake Fluid: If the racetrack beckons, this advanced formula is your ally. Designed for racing motorcycles, it provides exceptional lubrication and boasts a high boiling point of 312°C, ensuring resistance to vapor lock, fade, and the formation of steam bubbles. This brake fluid plays well with both ABS and non-ABS layouts, making it a versatile choice for a wide spectrum of motorcycles.

Liqui Moly 20154 DOT 4 Brake Fluid: This synthetic gem takes on oxidation at high temperatures and guards metallic brake components against corrosion. It’s ideal for hydraulic clutch systems and synthetic hydraulic fluid applications, demonstrating moisture resistance and compatibility with both conventional and ABS brake systems. Its impressive attributes include high thermal stability, low-temperature performance, and elastomer compatibility, surpassing various industry standards.

To those with a taste for the extraordinary, we present some special mentions:

Ipone 510 DOT 4 Brake Fluid: Tailor-made for motorcycles, this fluid thrives in extreme temperature conditions while adhering to DOT 4 standards. It combats vapor lock, prolongs the life of brake system components, and ensures impeccable braking performance.

Spectro I.SRBF Dot 4 Racing Brake Fluid 600: For the racers at heart, this premium racing brake fluid takes center stage. Crafted to withstand the rigors of high-performance motorcycles, it goes above and beyond DOT 4 specifications with a dry boiling point of 321°C. Vapor lock is but a distant memory, and maximum stopping power is your constant companion.

Silkolene 800164728 Pro Race Brake Fluid: Blurring the lines between DOT 4 and DOT 5.1 standards, this unique formulation combines excellent boiling resistance, vapor lock prevention, and consistent braking performance, delivering exceptional results even in the most demanding riding conditions.

Now that you’re armed with knowledge about the finest brake fluids to safeguard your adventures on two wheels, let’s conclude by revisiting the crucial chore of changing your motorcycle’s brake fluid. Remember, this isn’t a task to be trifled with; it’s a matter of your safety on the road.

Here’s a concise guide on how to change your motorcycle brake fluid:

  1. Gather all necessary equipment.
  2. Locate your motorcycle’s brake fluid reservoir.
  3. Remove the old or used brake fluid.
  4. Refill the brake fluid reservoir with the appropriate fluid.
  5. Bleed the brakes to ensure optimal performance.
  6. Check the fluid levels and make necessary adjustments.
  7. Tidy up to ensure a clean and safe working environment.
  8. Test your brakes to confirm they’re functioning perfectly.

Changing your brake fluid is a pivotal facet of motorcycle maintenance, one that should never be taken lightly. The chemical properties of hydraulic fluid are your guarantee of precise and dependable stopping power. Neglecting this essential task, allowing contaminants to infiltrate your braking system, or disregarding the manufacturer’s recommendations is a recipe for disaster. So, never skimp on the care of your motorcycle’s brake fluid, adhering to the OEM-recommended intervals, conducting replacements after system repairs, or whenever a change in brake fluid color raises its cautionary flag.

And let’s not forget the environmental responsibility—dispose of old brake fluid in an eco-conscious manner by consulting your local waste management or recycling center. Your diligence ensures not only your safety on the road but also the well-being of our planet.