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Common Brake Adjustments

By Joe Wilson

When the braking system on a bicycle doesn’t function properly it’s both a displeasure to ride and can be quite dangerous. This article will focus on the examination and adjustment of cable actuated braking systems found on road, cyclocross and some mountain bikes. The primary focus will be on caliper, center-pull cantilever, and direct-pull v-type brakes.

Photo by Seattle Bike Supply

Cantilever brake.

Before attempting to service any rim-style brake system there are a few things that must be in order. First, the cable system must be in good working condition. If there’s excessive friction due to corrosion or damage to the brake cables, buy new ones. In addition to the cables, observe the condition of the wheels. More specifically, ensure the wheel sits firmly in the dropouts of the frame/fork and its trued and dished properly; if this is not the case, any adjustments made will be futile.

Some may find it easier to remove the tires/tubes from the rim, especially on bikes with larger tires that obstruct the view of the brake pad/rim interface. The tools you need to adjust brakes usually consist of a 5mm Allen key, 10mm open-end wrench and a small piece of sandpaper. Additionally, a Hozan 4th Hand tool allows you to pull the cable with one hand and tighten the cable anchor bolt with the other.

First, examine the pads for wear by loosening the brake cables, bringing the pads away from the rim. Most cantilever brakes will unhook via the straddle cable either at the brake arm or at the cable itself. For direct-pull brakes the cable will enter a “noodle” on the side of the arm. It’s designed so it can be unseated to release tension. Caliper brakes typically have a quick release on the caliper or at the lever.

Caliper brake.

Next, check the wear line of the pad. If it’s worn to the line it should be replaced. Also, if there are bits of metal embedded in the pad’s surface it should be replaced. Otherwise, lightly sand the pad surface and go to the next step.

When the brake lever is actuated the pads should approach the rim uniformly and contact it evenly. If they don’t, adjustment is necessary. Most brake sets have a way of adjusting the pad position either integrated into the brake post mount or via a set of concave and convex washers on the post of the brake pad. I recommend loosening the pad just enough to allow for slightly labored movement.

Adjust the height so the pads approach and contact the rim surface squarely. They should not overlap the rim in either direction or contact the tire or extend below the rim. Adjust the angle of the pads so when viewed from the side the contour of the pads follow the contour of the rim. Adjust the “toe” of cantilever brake pads so the front of the pad contacts the rim first; a couple of millimeters is usually sufficient - skipping this step may cause an annoying squeal when you go to slow down or stop.

Photo by Seattle Bike Supply

V Brake

Direct pull v-type pads are designed to operate without toe, and, generally speaking, caliper brakes should be set with zero toe. However, a squealing brake sometimes warrants toeing of the pads on caliper brakes as well.

How far the pads extend from the brake arms is usually not an issue for direct pull v-brakes and caliper brakes. V-type brakes typically have two washers that are of different sizes, allowing some adjustment of the extension. If the arms are too close to the tire or wheel, the thicker washer should be positioned on the inside and the thinner one on the outside. If the arms are positioned too far outboard, the location of the washers should be reversed.

Center-pull cantilever brakes with post mount style brake pads will require the most attention. Generally, it’s good to position the pad close to the brake arm. On some newer low-profile style brakes, it will be necessary to utilize a fair amount of extension.

Once the above adjustments have been finalized, tighten the brake pads to ensure that they do not move.

The centering adjustment provided on most brakes is adjusted via a Phillips head or an Allen head near the brake post. Tightening the screw will increase tension and loosening will decrease tension. If the pad is closer to one side than the other and all other adjustments are in order, tighten that side. Maintain a balance on both sides while centering the brake. Dual pivot caliper brakes have an adjustment on the caliper to center the brake.

It is important to make sure the cable tension is where you prefer the lever throw (how hard you have to squeeze to engage the brakes). The cable can be pulled to adjust lever throw at the cable anchor bolt by loosening the bolt, then the pulling cable then re-tightening the anchor bolt. This is where the Hozan 4th hand is useful.

A properly adjusted brake will make cycling a more enjoyable experience. Be sure to periodically check your brakes for excessive wear or damage. If there are any questions that arise in the course of adjustment that are not explained in this article, consult a professional bicycle mechanic.

Joe Wilson is a professional bike mechanic at River City Bicycles in Portland, OR. He is also an event mechanic for Best Buddies Int’l. and a race mechanic for team Mosaic Smalti. He may be reached at josephwilson81@gmail.com