Are the brakes on your bike starting to feel a little loose? Perhaps you almost hit the curb because your bicycle didn’t stop in time?
No matter your situation, knowing how to adjust bike brakes is imperative to ensure your safety while on the road.
Today, I’m sharing two how-to guides for caliper and disc brakes. These include everything you need to know about bicycle brakes and how to adjust them.
Here’s a quick run-through of how to adjust bike brakes:
- Check the brake pads.
- See where the pads hit the rim.
- Loosen the brake pads.
- Position the brake pads.
- Test the tightness of the cable.
- Loosen the barrel adjuster.
- Unscrew the bolt holding the cable to the caliper.
- Pull the cable to tighten.
- Re-tighten the bolt.
- Tighten the barrel adjuster.
How to Adjust Bike Brakes — Caliper Brakes
Caliper bike brakes are those using brake pads controlled by a lever and caliper. These are simple to adjust.
For this job, all you need is an Allen wrench.
Step 1: Check Your Brake Pads
Before anything else, it’s important that you inspect the brake pads.
The first thing to check is if they’re worn down. All pads have a line labeled ‘wear line.’ Once the material reaches beyond this line, it’s time to replace the pads.
However, keep in mind that some brake pads have indentations as opposed to a written label.
The next thing to inspect is if the wheel lines up with the dropouts. If not, it will compromise your braking time.
Step 2: See Where the Pads Hit the Rim
Next up, check where the pads touch the rim. To do this, pull the lever while looking at the brake pads. Both should touch the center of the rim simultaneously with an equal amount of space above and below.
If the pads hit either too high or low, they may touch the wheel itself, or the spokes—the metal lines reaching the wheel’s center. When they do this, the brakes become almost useless.
Step 3: Loosen the Brake Pads
With an Allen wrench, loosen the bolts that hold the pads in place.
Insert into the hole, and turn counterclockwise to loosen them. Avoid releasing them all the way; otherwise, the brake pads will fall out of the holder completely.
Step 4: Position the Brake Pads
Position the pads so that they’re centered on the rim—not too high and not too low. Then place your thumb where you insert the screw to hold it in place.
Next, grab your Allen wrench and turn it clockwise to re-tighten the bolts. Check again to ensure that the brake pads are centered—if not, loosen again and re-adjust.
Step 5: Test the Tightness of the Cables
Pull the levers and assess the distance between the lever and the handle of the bike. There should be approximately 1.5-inch between the grip and lever—roughly two fingers.
If the levers touch the handle, they’re far too loose, and won’t be able to stop your bike efficiently.
Step 6: Loosen the Barrel Adjusters
If your cables aren’t too loose, all you need are minor adjustments. To do this, simply loosen the barrel adjuster—the part sitting where the cables meet the levers.
To loosen it, turn it counterclockwise. As you loosen the barrel adjuster, you’re actually tightening the cable slightly. So, check the lever—if it’s tight, you’ve fixed the problem and can re-tighten the barrel.
However, if it still feels too loose, the issue is probably on the caliper. So, leave the barrel adjuster without re-tightening it and move to the next step.
Step 7: Unscrew the Bolt Attaching the Cable to the Caliper
Locate the bolt sitting at the front of the caliper, keeping the brake cable in place. Use your Allen wrench to loosen it by turning counterclockwise.
Avoid unscrewing it all the way. Simply rotate a few times to loosen it slightly—perhaps two or three times.
Step 8: Pull the Cable to Tighten
Grab the cable and pull gently outward to tighten it. Hold it using your fingers once it’s taut.
As you pull, notice that the brake pads tighten around the rim of the tire. Then, spin the tire slightly—there should be some resistance. However, not so much so that the wheel can’t move.
If it’s too tight, loosen the cable slightly again, and then check that the wheel turns.
Step 9: Re-Tighten the Bolt
Use your Allen wrench to re-tighten the bolt on the caliper. Turn it clockwise until it won’t turn more.
Step 10: Tighten the Barrel Adjuster
Move back up to the barrel adjuster by the lever. Turn it clockwise to tighten it fully.
As you tighten the barrel adjuster, the brake pads loosen their grip on the rim just enough to make a perfect fit.
Now you can test the brakes. Pull the lever and check that there are no less than 1.5-inch or two fingers between the grip and lever clamp. Then, congratulations, you’re all done.
How to Adjust Bike Brakes — Disc Brakes
Disc brakes are another common type of brake. They work by having two pads press on both sides of the wheel’s rotor, slowing the bike.
There are two types of disc brakes: hydraulic and mechanical. However, adjusting them is relatively easy, and you won’t need any fancy tools.
Before You Start
With disc brakes, whether hydraulic or mechanical, it’s essential to take a few minutes to prep and check the wheel:
Step 1: Assess the Brakes
Before we start meddling with the brakes, flip your bike upside down or place it on a stand. When adjusting disc brakes, the wheels should always be off the ground, allowing them to spin freely.
Then if you’re unsure whether you have a hydraulic or mechanical disc brake, now is the time to check.
Hydraulic disc brakes don’t have cables running through the caliper, whereas mechanical do.
Step 2: Tighten the Wheel
Before adjusting the brakes, you need to tighten the wheel in the drop house—the Y-shaped frame attaching the wheel to the frame.
To tighten, grab the lever sitting on the side of the wheel and turn it clockwise. Then fold it back so that it’s flush with the tire. Some older bikes may require you to use an Allen wrench.
However, be careful not to cut yourself on the rotor—it’s sharp!
Adjusting Hydraulic Disc Brakes
If you have hydraulic disc brakes—without cables—this is your section.
Step 1: Loosen the Caliper Bolts
If the disc brake is rubbing against the wheel as you ride, the two bolts sitting on the caliper are too tight.
Find the 1/8-inch hex bolts holding the caliper to the frame. Then with your Allen wrench, twist each bolt a half-turn counterclockwise.
Keep in mind that it may not always be too tight on both wheels—one might be fine.
Step 2: Center the Caliper
Pull the brake lever two to three times and watch if the caliper centers on the rotor. Make sure you’re looking at the corresponding wheel.
On the last pull, continue squeezing the lever as you re-tighten the bolts. Do a half-turn using the Allen wrench. Then let go of the brake lever, and do the same on the other wheel if applicable.
However, if the caliper doesn’t center when you pull the lever, you can do it manually.
Gently move the caliper so that it centers, and continue holding it in place while you re-tighten the bolts.
Step 3: Spin the Wheel
Check if the rubbing has stopped by spinning the wheel. Listen for any indication that it may still be too tight. If there is no sound, you’ve completed the task.
Adjusting Mechanical Disc Brakes
If your brakes have cables, here’s the section for you. For this round, you need an Allen wrench and potentially a Phillips-head screwdriver.
Step 1: Loosen the Screw
Begin by loosening the small set screw sitting on the side of the caliper. Use the Phillips-head screwdriver and turn it one to two full rotations counterclockwise.
If your bike doesn’t have a set screw, simply skip this step.
Step 2: Twist the Adjustment Dial
Manually twist the adjustment dial, sitting on the side of the caliper. It’s about 1-inch wide and made of plastic, sitting right next to the spokes.
Turn the dial clockwise to tighten and counterclockwise to loosen. Continue adjusting it until the caliper is centered on the rotor. Give the wheel a spin sometimes to ensure it isn’t too tight.
Some bikes don’t have a manual dial, so you’ll need an Allen wrench to turn it.
Step 3: Pull the Brake Lever
Pull the lever for the corresponding wheel to ensure the pads tighten around the rotor. The pads should touch the rotor simultaneously. Then check the other wheel.
If the pads don’t touch simultaneously, then go back and re-adjust the dial.
Step 4: Tighten the Hex Bolts and Set Screw
Before you go for a ride, tighten the set screw and hex bolts using your screwdriver and Allen wrench.
Even if you didn’t touch the hex bolts, you should still tighten them until they won’t turn anymore.
Now, you should be ready to go!
Let's Take a Brake
Knowing how to adjust bike brakes is important. In case you get stuck somewhere or don’t have access to a mechanic, you know what to do. And luckily, it’s a fairly straightforward process.
There are several types of brakes. But the most common are either caliper or disc brakes, which is what I focused on today.
Remember, always ensure that your brakes aren’t too tight or loose. Check the levers and make sure the brakes center on the rotor and rim.