The majority of bicycles use Shimano brakes. They're easy to adjust on the trail, road, or in your garage at home using simple tools. Four types of mechanical brake systems typify Shimano's line-up: The V-brake on mountain bikes, the dual pivot or side pull on road bikes, and the mechanical disc brake are easy to adjust. A fourth type, the hydraulic disc brake, operates with fluid, and typically requires bleeding when it gets mushy or soft.
V-Brake and Dual Pivot Pad
1. Turn a hex bolt, using a 5 mm hex wrench, counterclockwise to loosen the brake pad. The hex bolt is located horizontally on the brake housing, facing away from the wheel.
2. Slide the brake pad up or down to center it on the rim. Do both sides.
3. Tighten the hex bolt lightly on both sides. Squeeze the levers on both sides of the wheel to compress the pads against the rim, and hold them there. Check the alignment of the pads and adjust them again if necessary to center them on the rim. Loosen the hex bolt if needed to move the pad. When the pad is centered, tighten the hex bolt securely.
V-Brake and Dual Pivot Barrel Adjuster
1. Turn the barrel adjuster counterclockwise to tighten the brake cable. The barrel adjuster is a knurled knob where the cable enters the lever housing.
2. Grasp the brake lever and apply the brake. If the brake handle touches the handlebar or feels soft, continue turning the barrel adjuster until the brake handle feels stiff, and applies sufficient pressure to the pads.
3. Tighten the knurled washer, located on the end of the barrel adjuster, with your fingers to secure the barrel to the brake lever housing.
V-Brake and Dual Pivot Cable Adjustment
1. Loosen the cable hex bolt using a 5 mm hex wrench. The bolt is located on one side of the brake calipers or arms, above the wheel. The brake cable passes behind, or under the hex bolt depending on the type.
2. Squeeze the brake arms together with your fingers. Grasp the bullet-shaped knob at the end of the cable, and pull the cable tight.
3. Tighten the hex bolt to secure the cable.
Mechanical Disc Brake
1. Insert a 3 mm hex wrench into a horizontal setscrew on the outside of the brake housing. Turn the setscrew 1/4-turn counterclockwise.
2. Insert a .0012 feeler gauge between the disc brake and the brake pad. If it's too tight, and the feeler gauge won't fit without force, turn the hex wrench another 1/4-turn.
3. Slide the feeler gauge back and forth while tightening the setscrew slowly. When the feeler gauge begins to drag moderately when you move it, stop turning the setscrew.
4. Insert the 3 mm hex wrench through the spokes to adjust the inboard setscrew -- the setscrew on the inside of the brake housing. Turn the inboard setscrew 1/4-turn to loosen it. Repeat Steps 2 and 3.
Items you will need
- 5 mm hex wrench
- 3 mm hex wrench
- Feeler gauge
- Barrel adjusters and cable tightening work together. It's sometimes necessary to readjust one or the other to compensate for a previous adjustment.
- If your brake pads squeak when you apply the brakes, readjust the pad so that the front of the pad touches the rim before the back.
- Check all adjustments for tightness before riding the bike.
- YouTube: Santa Fe Mountain Sports: Adjusting a V-Brake
- YouTube: Adam Loretz: How to Check the V Brakes on Your Mountain Bike
- YouTube: Richpin: Adjusting Bicycle Disc Brakes
- YouTube: Bikewagon.com: Adjusting Side Pull Brakes / Road Bike Brakes
- Shimano: Technical Service Instructions V-Brake
- Shimano: Service Instructions: Caliper Brake
- Shimano: Disc Brake System For Cross Country
- Cristian Mihai Vela/iStock/Getty Images