Garage Files – How To Silence Honking Brakes
This is one of the most common and most annoying problems you can experience. Your bike, which is otherwise perfectly dialed in and shifting like a machine gun, also sounds like a homesick goose every time you hit the brakes. Either that, or the brakes rub so badly they slow you down, in addition to making that awful grinding noise. Anyone who’s cursed a pinging brake rotor knows what we’re talking about here. Even if the brake isn’t rubbing hard enough to really slow you down, it’s still enough to cause a psychological impact, making you think you’re being robbed of power. Strong, consistent and quiet brakes will help you descend better, and brakes that don’t rub will help you climb better. We’ll show you how to dial in your brakes to find the best of both worlds.
1-The most common cause of brake noise is contamination of the rotors. This is when fluids that aren’t supposed to be on the pads or rotors get there and cause vibration and a lack of friction.
2-Brake pads are porous. They are essentially metallic back plates with brake-pad material attached to them. No matter what pad material you’re using, if you get chemicals like chain lubes, certain degreasers or frame polish on them, they will more than likely need to be replaced.
3- Let’s start by suggesting how not to contaminate your pads in the first place. Lubricating your chain is critical to keeping the drivetrain running smoothly. However, that same lubricant will wreck your pads. Aerosol lubricants are usually to blame for the overspray that can damage pads.
4-If you absolutely must use aerosol lubricant, be sure to keep a paper towel or shop rag behind the chain as you apply it. This will catch most of the overspray and keep it from landing where it doesn’t belong.
5-We prefer to use drip lubricants, which have basically no chance of contaminating the brake pads. Bonus points if you put one drop of lube on each link, and then carefully wipe the chain off when you’re done.
6-When using a frame polish, avoid spraying the chemical directly on the frame. The overspray will, again, likely contaminate the brake pads.
7-Instead, spray the polish directly on the towel, and then use the damp towel to polish the frame. As an added bonus, we’ve found that this method uses much less of the chemical per polish with the same results, and our polish cans last longer.
8-When bleeding your brakes, it’s easy to get lazy and think, it’ll never spill. This will almost always lead to a sprayed hose fitting or drips on the rotor.
9-Instead, do it the right way, and always remove the wheel and pads from the bike when bleeding brakes. Use the brake bleeding block most brakes come with to keep the pads properly spaced when bleeding. If you don’t have one, head to your favorite shop mechanic and beg for one, then cherish it when he kindly gives it to you.
10-It’s even possible to contaminate pads when washing your bike. If you wash your bike with a hose, be sure to have a separate brush for the drivetrain. Even then, avoid scrubbing the brake rotors.
11-If you do end up with contaminated pads, the sound will be a “honking” noise every time the brake is applied with any force.
12-This can sometimes be remedied by taking the top layer of the pad material off with a file. To do this, remove the pads from the brake caliper like so.
13-Then, lay the pad on the workbench, and file off the top layer until the color of the material changes and is consistent on the entire surface area.
14-Then, prior to reinstalling, be sure to clean the rotors thoroughly. For this you can use isopropyl alcohol. We also have had great luck with Maxima Suspension Clean for this job. Be sure to use a fresh paper towel for this, as any leftover chemicals on a shop rag can do more damage than good.
15-After this cleaning process you will likely need to re-burnish the pads so that they get accustomed to the rotors, transfer some of the pad material and realign themselves with the rotors. This is as easy as heading out for a quick test ride and doing 30–40 firm brakes.
16-If this doesn’t work, you’re looking at a fresh pair of brake pads as the only solution. We’ve had excellent luck with TruckerCo’s pads, which will be installed on this lucky bike.
17-If honking isn’t your issue, it’s likely a simple brake adjustment that your steed needs. You can sight from the top of the brake caliper to see how the alignment is. Ideally, you should be able to see daylight between the rotor and both pads.
18-When the wheel is spinning, it’s normal to see the rotor “wobble” a little. If it’s wobbling enough that it’s hitting both sides of the pads, you may need to true it.
19-You can use a clean crescent wrench for this job, but we prefer a dedicated rotor truing tool, like this one from Wolf Tooth Components.
20-To adjust the brake, start by loosening both of the caliper mounting bolts that run parallel to the wheel.
21-To use the quick, “cheater” way, you can simply squeeze the brake lever to center the caliper and snug the bolts down.
22-Give the wheel a spin and see if the rotor is still pinging. If it’s running smooth, you’re ready to hit the trail.
23-If not, loosen the caliper mounting bolts and simply manually center the caliper over the rotor. It’s very important to not do this while the wheel is spinning. The caliper is very close to the rotor and is very sharp. If you catch your finger in a spinning rotor, it will lop off the end of it without even slowing down.
24-Check your work, readjust if necessary and go hit the trails.
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