Motorcycle brake issues, not something you ever want to experience, but something you need to be mindful of. Your motorcycle’s braking system is one of its most critical components when it comes to safety. You already know that! However, like any part of a bike, brakes wear over time, and this will mean you won’t hit that next apex, or get around that next corner as you want… Whether you’re hearing strange noises, feeling a lack of stopping power, or noticing leaks, you should address these signs as soon as you feel or see them.
But what are you feeling for?
In this blog, we’ll go over six of the most common issues and signs that something is wrong with your motorcycle brakes. From squeaky or spongy brakes to brake fluid leaks and more, we’ll explain what’s causing the issue and, more importantly, how to fix it.
Proper maintenance (although not always fun) not only ensures a safer ride but also prevents small issues from turning into costly repairs. Let’s dive into these common symptoms and their solutions to keep your motorcycle braking smoothly and safely.
6 things to look out for (Brief overview)
If you’re short on time, we have done the heavy lifting already. Here’s a quick breakdown of common brake issues and their solutions. For a more in depth explanation of each one, continue reading…
Squealing or Squeaking Sounds:
Cause: This could be due to worn brake pads, a glazed disc or brake pads, or dust and debris build up.
Fix: Replace worn pads, clean glazed pads and discs with fine sandpaper, and lubricate the callipers and pistons to ensure smooth operation.
Spongy Brake Lever/Weak Braking:
Cause: Air in the brake lines, low brake fluid, or worn brake pads.
Fix: Bleed the brakes to remove air, check for fluid leaks, and top up or replace brake fluid. Replace worn brake pads immediately.
Brake Fluid Leaks:
Cause: Leaks can occur due to damaged brake lines, seals, or the master cylinder.
Fix: Identify the leak source, tighten hose clamps, or replace damaged seals or hoses. Rebuild or replace the master cylinder if needed.
Vibration When Braking:
Cause: Warped discs or uneven brake pad wear.
Fix: Check for warped discs and replace if necessary. Replace unevenly worn brake pads and check callipers for proper function.
Brake Fade:
Cause: Overheating, degraded brake fluid, or contaminated fluid.
Fix: Flush the brake fluid to replace old or contaminated fluid. Consider upgrading to high-performance brake fluid if overheating is an issue.
Motorcycle Pulling to One Side:
Cause: A seized or unevenly functioning calliper.
Fix: Clean and lubricate the callipers regularly. If the problem persists, rebuild or replace the callipers.
Motorcycle Brake Issues and Causes (In depth look)
If you’ve experienced or are experiencing any of these then you will know how uncomfortable and disconcerting it is to ride. But don’t fret, there are plenty of easy things you can do to help which will give you that confidence back!
Continue reading for in depth analysis on all 6 of the most common types of motorcycle brake issues and how you can fix them easily…
Squealing or Squeaking Sounds
If your bike makes a high pitched squeal or screech when braking, it’s a sign that something is amiss with the system. This can be the case even if your brakes are working properly. This is worth fixing because as well as being annoying, it can compromise your safety.
Causes of squealing and squeaking brakes
Worn Brake Pads:
What Happens: As brake pads wear down, the friction material becomes thinner. Once it gets too thin, the metal backing plate of the brake pad can begin to contact the disc, creating a squealing sound. This is a clear sign that the brake pads need to be replaced.
Fix: Replace the brake pads. Inspect the discs for damage (like deep grooves) that may also need attention when the pads are worn through to the metal.
Glazed Brake Pads or disc:
What Happens: Brake pads or discs can become glazed due to excessive heat, often caused by heavy braking or riding conditions that demand constant braking (e.g., downhill or stop-and-go traffic). When this happens, a smooth, hard layer forms on the pads or disc, reducing friction and causing a squeaking sound.
Fix: Remove the brake pads and use fine sandpaper (500-600 grit) to sand off the glazed layer. Also, lightly clean the disc surface with some fine wire wool and brake cleaner. After cleaning, reinstall the pads and ensure proper bedding to avoid future glazing.
Debris Build Up:
What Happens: Dirt, dust, or small debris can get trapped between the brake pads and disc, which can cause noise as the brake pads rub against the foreign material.
Fix: Clean both the brake pads and the disc. Remove the pads and carefully clean them using sandpaper, and clean the disc with an appropriate brake cleaner.
Lack of Lubrication on the calliper Components:
What Happens: Over time, the calliper can become stiff or less responsive if the guide pins (which allow the calliper to move freely) or pistons (which push the pads onto the disc) become dirty or corroded. This can result in the pads not retracting properly from the disc, causing a squeak.
Fix: Clean and lubricate the calliper guide pins and pistons with high-temperature silicone grease or specific brake lubricant. Regular maintenance of these components will prevent this from happening in the future.
Environmental Factors:
What Happens: Sometimes, external conditions like moisture after rain or cold weather can cause temporary squealing. Moisture creates a thin layer between the brake pads and disc, which can result in noise until it burns off during braking.
Fix: In many cases, this resolves on its own as the brakes heat up and dry the moisture. However, if the noise persists, further inspection of the pads and disc is necessary.
Why it’s important to fix
Even though squealing may not always affect the immediate stopping power of your motorcycle, it’s crucial to address the underlying cause. Ignoring this issue can lead to more severe damage, like disc wear, and can compromise the overall effectiveness of your brakes in the long term.
By keeping your brakes clean, well-maintained, and free of contaminants, you ensure not only a quieter ride but also a safer one. Regularly inspecting brake pads and replacing them when necessary, along with keeping callipers and pistons lubricated, will help prevent these issues from recurring.
Spongy Brake Lever/Weak Braking
Imagine you’re squeezing the brake lever or pressing the pedal, and it just feels soft, like it lacks resistance, and the bike doesn’t stop as quickly as you’d expect. This isn’t something you want to experience, right?
What’s Going On?
The term “spongy” usually means that there’s a lack of firmness when you apply the brakes. This could be due to several things, but the two most common culprits are air in the brake lines or low brake fluid levels.
Air in the Brake Lines
Think of your brake system like a sealed circuit, where brake fluid transfers force from the brake lever to the brake callipers, which then clamp the pads onto the discs. Now, brake fluid is incompressible, which means it transmits this force very efficiently. But if there’s air in the brake lines, things go wrong because air compresses, so instead of a firm feel, you get that squishy, weak response.
Fix: You’ll need to bleed the brakes. This involves removing the trapped air from the brake lines. It’s not too difficult to do, and if you’ve got a manual or video tutorial handy, it’s a manageable DIY task. Essentially, you’ll be opening the bleed valves on the callipers and pumping fresh brake fluid through until the air is purged.
Low or Contaminated Brake Fluid
Brake fluid doesn’t last forever. Over time, it absorbs moisture from the air (it’s hygroscopic), which lowers its boiling point and causes it to become less effective. The fluid can also leak out due to cracks in the brake lines, worn seals, or a faulty master cylinder. When the fluid level drops, you won’t get enough hydraulic pressure to operate the brakes properly.
Fix: Start by checking the brake fluid reservoir. If the fluid looks dark or murky, or if the levels are low, you’ll want to top it up or, even better, do a complete fluid flush. Replacing old fluid with fresh fluid will restore the proper hydraulic pressure and get your brakes working like new again.
Worn Brake Pads
Another possible reason for that soft, ineffective braking feel is simply worn brake pads. Over time, pads wear down and become too thin to properly grip the discs. This not only reduces braking power but can also create that “spongy” feel since you’re essentially trying to stop the bike with minimal material left on the pads.
Fix: If the pads are worn, replace them. Check the discs too, because if the pads were too worn for too long, the discs might have taken some damage as well, which would need resurfacing or replacement.
Checking for Leaks
If you suspect a leak, it could be anywhere in the brake system – brake lines, callipers, or master cylinder. Fluid leaks would not only lower the brake fluid level but also allow air to enter the system, which compounds the spongy feel.
Fix: Inspect the brake lines for any visible leaks, especially around fittings and connections. If you find a leak, you might need to replace the lines or seals. Make sure to thoroughly clean and dry the area so you can pinpoint where the leak is coming from.
Why it’s important to fix
A spongy brake feel is definitely something you don’t want to ignore. At best, it’s an annoying distraction, but at worst, it’s a major safety issue. So, whether it’s a simple fix like bleeding the brakes or topping off the fluid, or something more involved like replacing parts, it’s worth taking care of quickly.
Brake Fluid Leaks
Let’s talk in more detail about brake fluid leaks, as they can significantly compromise the safety and performance of your motorcycle’s brakes. When you press the brake lever or pedal, brake fluid is what transfers the force from your input to the brake callipers, which then apply pressure to the pads and disc to slow you down. Any issue with the brake fluid will affect this process, so leaks are a big red flag.
Why Brake Fluid Leaks are Dangerous
When there’s a brake fluid leak, the braking system can’t generate enough pressure to stop the bike effectively. This reduces braking power, leading to longer stopping distances or, in the worst case, brake failure. Even a small leak can lead to air entering the system, which weakens the hydraulic pressure, making the brakes feel “soft” or unresponsive.
Causes of Brake Fluid Leaks
Brake fluid leaks can stem from several areas, including:
Damaged Brake Lines
Over time, brake lines can crack or wear out, especially if they’re made of rubber. Metal brake lines can also corrode. These cracks or corrosion points allow brake fluid to escape.
Worn Seals
In your master cylinder or callipers, there are rubber seals designed to keep the brake fluid contained. Over time, these seals can dry out, crack, or wear down, leading to leaks.
Loose Connections
The points where the brake lines connect to the master cylinder or callipers use fittings or banjo bolts. If these aren’t secured tightly or if washers (often crush washers) become worn, fluid can leak around these connections.
Master Cylinder Issues
Sometimes, the master cylinder itself can develop leaks due to internal wear, especially if the bike has aged or seen a lot of hard riding. The cylinder’s O-rings or gaskets can fail, allowing fluid to seep out.
Signs of Brake Fluid Leaks
Low Brake Fluid Level: If you’re topping off the brake fluid frequently, but it keeps getting low, you likely have a leak somewhere.
Visible Fluid: You might notice brake fluid around the wheels, on the brake lines, or around the master cylinder. Brake fluid is usually clear or slightly amber, and it’s slightly oily to the touch.
Spongy Brakes: A soft brake lever or pedal feel could indicate that air is entering the system due to a fluid leak.
How to Fix Brake Fluid Leaks
Inspect and Identify: The first step is to find the source of the leak. Start by checking around the master cylinder, brake lines, and calliper fittings for any visible fluid. If you can’t see the source immediately, cleaning the area and then rechecking can help you locate the leak.
Tighten Connections: If the leak is at a fitting or banjo bolt, try tightening these connections. Ensure that crush washers, which seal these connections, are replaced if they are worn out.
Replace Brake Lines or Seals: If the brake lines themselves are cracked or the seals in the callipers or master cylinder are worn, you’ll need to replace these components. Replacing the brake lines can be a straightforward job if you’re comfortable working with brakes, but for calliper or master cylinder seals, you might want to consider a rebuild kit or professional help.
Bleed the Brakes: Once the leak is fixed, you’ll need to bleed the brake system to remove any air that has entered and restore proper pressure. This ensures that the brake lever or pedal feels firm and responsive again.
Preventing Future Leaks
Regularly inspect your brake system, including lines, seals, and connections, especially if your bike is older or has been ridden hard.
Replace brake fluid at regular intervals (usually every one to two years) to prevent moisture contamination, which can cause internal corrosion and degrade seals.
Why it’s important to fix
By staying on top of these inspections and addressing leaks as soon as they appear, you can keep your motorcycle’s brakes functioning safely and reliably.
Vibration When Braking
This one is pretty easy to feel—when you pull the brake lever or step on the pedal, the bike should slow down smoothly, but instead, you feel a shudder or vibration coming through the handlebars or foot pegs. Not only is this uncomfortable, but it’s also a sign that something’s wrong with your braking system that needs attention.
What Causes Vibration When Braking?
Warped discs
The most common reason for vibration is warped brake discs. When the discs are perfectly flat, the brake pads can grip them evenly, resulting in smooth braking. But over time, heat generated from braking can cause the discs to warp slightly. It only takes a small amount of warping to make a big difference—you’ll feel a pulsing or shaking as the pads hit the high and low spots on the disc during braking.
Fix: If the discs are warped, you’ll need to replace them, depending on how bad the warping is. It’s important to address this early because continuing to ride with warped discs can lead to uneven wear on the pads and even more expensive repairs.
Uneven Brake Pad Wear
Another cause of vibration can be uneven brake pad wear. If one side of the brake pad wears down faster than the other, it can create an imbalance when you brake. This might happen if the calliper isn’t applying even pressure to both sides of the disc, or if the pads themselves aren’t seated correctly.
Fix: First, check the condition of your brake pads. If they’re uneven, replacing them should solve the issue. But also take a look at the callipers to make sure they’re functioning properly. Sometimes, callipers can stick due to dirt or corrosion, causing one side to grip more tightly than the other.
Loose or Worn Suspension Components
Although this is less common, vibration during braking can also come from issues with your bike’s suspension or steering components. If parts like the front forks, steering head bearings, or wheel bearings are worn or loose, it can cause instability that’s felt more strongly during braking.
Fix: Check for any play or movement in the front end when you push on the handlebars with the bike stationary. If you notice any wobbling or knocking sounds, it’s time to tighten or replace the affected components.
Improperly Installed Brake Components
Sometimes, vibration occurs simply because the brake system wasn’t assembled correctly. For example, if the brake discs weren’t torqued down to the correct specifications, or if the pads weren’t seated properly, you might experience vibration even with new parts.
Fix: If you’ve recently had brake work done and you’re now feeling vibration, it’s a good idea to double-check the installation. Make sure all bolts and fasteners are torqued to the manufacturer’s specs and that the pads are seated evenly.
Why it’s important to fix
Vibration when braking is usually a sign that something’s not right with your bike’s braking system, and ignoring it can lead to more serious issues down the road.
Brake Fade (Loss of Brake Effectiveness)
When you’re riding and suddenly notice that your brakes don’t have the same bite or stopping power they did earlier, it’s often due to brake fade. This usually happens after a lot of hard or prolonged braking, like when you’re pushing on a track or even if you’re going downhill for an extended period.
Brake fade typically occurs for two main reasons:
Overheated Brake Pads:
When the brake pads get too hot, they can’t generate as much friction as they should. It’s a bit like trying to stop with a slippery surface between your pads and discs. This heat can glaze the pads, making them ineffective until they cool down. You’ve probably noticed this happening if you’re pushing your bike hard, like on a track day, but it can also happen on the road. The pads just get too hot to do their job.
Fix: If you’re consistently experiencing this, consider upgrading to brake pads that are better suited for high heat. Pads with a higher temperature tolerance, like semi-metallic or carbon pads, might be the solution if you’re doing a lot of aggressive riding.
Brake Fluid Overheating:
The other side of the coin is brake fluid overheating, or fluid fade. This happens when the fluid inside your brake lines boils due to excessive heat, particularly if it has absorbed moisture over time (brake fluid is hygroscopic, so it naturally attracts water). When the fluid boils, it creates air bubbles, which compress when you pull the lever. This results in a soft or spongy feel, and your brakes don’t respond as sharply as they should.
Fix: A fluid flush and replacement with fresh, high-performance brake fluid (like DOT 4 or 5.1) is often a quick fix. This helps maintain consistent pressure and ensures your brakes perform better under stress.
Why it’s important to fix
To put it simply, you want this fixed to give you back confidence on the bike. Brake fade can be one of the most disconcerting things you can experience, imagine just losing brake performance while riding… you’ll want to avoid this im sure.
If you need to know more about brake fade, the causes, types and how to stop it happening, we have delved into it on our blog.
Motorcycle Pulling to One Side
It’s a pretty noticeable and unsettling problem—you’re cruising along, hit the brakes, and instead of slowing down in a straight line, the bike veers off to one side. Not exactly ideal, right?
What’s Causing the Pull?
This issue typically points to an imbalance in your braking system, meaning one side of your brakes is working harder than the other. There are a few reasons this might happen:
Stuck or Seized Calliper
A common cause of pulling to one side is a stuck or seized brake calliper. The calliper is responsible for pushing the brake pads onto the disc, and if it’s not moving freely or evenly on both sides, it could cause one side to grip harder than the other. That imbalance pulls the bike toward the side with more braking force.
Fix: You’ll need to clean and lubricate the calliper’s moving parts, like the guide pins. If the calliper is damaged or corroded beyond cleaning, it might need to be rebuilt or replaced.
Uneven Pad Wear
Another reason could be that your brake pads are wearing unevenly. If one side of your brake pads is thinner than the other, you won’t get even braking pressure, and that can also cause the bike to pull to one side when you brake.
Fix: Check the pads for uneven wear and replace them if necessary. At the same time, make sure the calliper is working properly, as that’s often the root cause of uneven wear.
Brake Fluid Issues
If your brake fluid is low or there’s air in the lines, it could cause one side of your brakes to be less effective. This uneven pressure between the two sides can also result in the bike pulling to one side.
Fix: Bleed the brakes to ensure no air is in the system and check for any leaks. Also, make sure the fluid level is where it should be.
Wheel Alignment or Suspension Problems
Sometimes, it’s not just the brakes. If your wheels are out of alignment or there’s an issue with the front suspension, it could cause the bike to pull when you apply the brakes. This is less common, but it’s worth checking if everything else seems fine.
Fix: Inspect the wheel alignment and suspension components for any wear or damage. If necessary, adjust or replace any misaligned parts.
Why It’s Important to Fix
Riding with a brake imbalance isn’t just annoying—it’s dangerous. You never know when you’ll need to stop in a hurry, and if the bike pulls unpredictably, it could put you in a risky situation. So, if you notice your motorcycle pulling to one side when braking, it’s a sign you need to inspect your braking system and possibly do some maintenance. It’s one of those issues that might seem small at first, but addressing it early can prevent bigger problems down the line.
In Summary
Now to be serious for a second, motorcycle brake issues can be worrying, but keeping your motorcycle’s braking system in top shape will keep your confidence levels high when out on the roads. Whether it’s squealing sounds, spongy brake levers, fluid leaks, vibration, brake fade, or the bike pulling to one side, each issue gives you clues that something needs attention.
Understanding the root causes and addressing them early can prevent more serious problems down the road. Regular maintenance, including checking brake fluid levels, replacing worn pads, cleaning callipers, and keeping an eye on disc condition, will keep your ride smooth and safe.
If any of the maintenance points mentioned feel out of your depth, definitely get in contact with our professional team. You want to be confident that your bike will stop when you need it to!
Enjoyed this? Read more on the Demon Tweeks blog:
- Motorcycle Brakes: The Ultimate Guide
- Understanding Motorcycle Tyre Markings
- Step By Step Guide: How to Change a Motorcycle Tyre
Where To Next?
Looking for the latest motorcycle parts and accessories? Check out our wide range from top brands.
Come and visit us at our store, showroom and fitting centre in Wrexham.
Want to know more about our story? Learn about who we are and why we’ve been driven by passion for over 50 years.
Interested in everything we do? Catch up on all the latest Demon Tweeks news.