Linear-pull (V-brake) adjustment - part identification

Brake Lever: mounting bolt, reach adjustment screw, pivot, barrel adjuster and lock ring.

Fig 1

Brake assembly: brake arms, mounting bolts, cable pinch bolt, return springs, centering screws.

Fig 2

Brake assembly (continued): noodle, cradle, boot.

Fig 3

Brake pad: mounting nut, concave/convex washers.

Fig 4

Last Updated: 11/20/2006.

Brake cable: end cap, ball end.

Fig 5

Brake cable housing: ferrules, housing stops.

Fig 6

Linear-pull (V-brake) pre-adjustment inspection

a) Check that the wheel is seated flush in the dropouts and is trued and centered.

Fig 7

Last Updated: 11/20/2006.

b) Check that the brake assembly is properly mounted, relatively centered, and that the brake arms move freely

without flopping. Check that return spring is in place and not broken. Also, make sure the spring is inserted into

the center hole on the brake boss (part of the frame where the brakes attach).

Fig 8

The mounting bolts should be snug, but not super tight.

c) Check the brake levers for damage, working barrel adjusters, mounting bolts, and working return

springs if applicable.

d) Check the brake housing for damage, sharp bends, and proper length to allow movement without sharp

bends. Make sure the cable stops on the frame are in good condition, and that there are ferrules on the

housing ends.

Fig 9

Last Updated: 11/20/2006.

Linear Pull (V-brake) Adjustment

1. Set lever position and angle (optional)

To a large extent, the position of the brake levers is a matter of personal preference. However, the following

procedure should be done if the levers are grossly out of position.

Fig 10

Loosen the mounting bolt/nut, position lever on handlebar and set at 45 degrees to the ground.

Tighten the mounting hardware.

Fig 11

Fig 12

Use the reach adjustment screw to set the distance between the lever and the handlebar to allow a comfortable reach. Turning it clockwise will move the lever closer to the bar.

Last Updated: 11/20/2006.

2. Adjust brake pads

It's important that the brake pads contact the rim squarely and in the center of the braking surface. A misaligned

pad may slide off the rim and into the tire or spokes.

Fig 13

Most linear-pull brakes use brake pads with convex and concave washers which allow them to be angled in any direction.

Also notice that there are two thicknesses of concave washer on each pad. That is so you can adjust how far the pads extend from the brake arms.

Fig 14

The pads should follow the curve of the rim.

Last Updated: 11/20/2006.

Fig 15

They should be centered vertically on braking surface of rim.

Fig 16

And they should contact the rim at a 90 degree angle to the braking surface.

Ideally, at the point of contact, the brake arms should be at a 90 degree angle to the pads as well. If your brake arms are at an extreme angle to the pads when the pads contact the rim, you may need to swap the washers on the brake pad.

Generally, brake pads are set up with toe-in. Toe-in means the leading edge of the pad touches the rim before

the trailing edge. This counteracts the torque imparted on the brake by the rim and stops squealing. The standard

amount of toe-in is 1mm (the trailing edge of the pad will be 1mm from the rim when the leading edge makes

contact).

Many linear-pull brakes, however, use asymmetrical pads which are designed to be used with no toe-in.

They don't require toe-in because the longer rear section of the pad resists the twisting forces exerted on it by the

wheel.

So the rule of thumb is, if you have asymmetrical pads set them up without toe-in and only add

it if necessary. If your pads are symmetrical set them up with 1mm of toe-in.

Fig 17

Symmetrical pads should have about 1mm of toe-in.

Last Updated: 11/20/2006.

Fig 18

Set asymmetrical pads so they are parallel to the rim when viewed from above.

(Pretend the pad in the picture is asymmetrical)

Fig 19

Brake pads should be adjusted one at a time. Loosen the brake pad mounting bolt just enough to allow the pad to move.

Keeping your wrench in the brake pad mounting bolt, manipulate the pad with your other hand.

Make small adjustments and check frequently by snugging up the bolt and pushing the brake pad against the rim while watching to see how it hits.

A method which can greatly simplify adjustment is to release the spring on the side you are adjusting and let

the spring in the other arm pull the pad against the rim.

Fig 20

The spring rests on a little knob on the brake arm. To disconnect it, push the spring in toward the wheel and move it to the side.

Last Updated: 11/20/2006.

Fig 21

The spring's pressure will open it away from the wheel.

The brake pad will be pulled against the rim by the spring in the opposite brake arm.

Now you all you have to do is adjust the pad so it makes even contact with the rim.

If you need to add toe-in you can use your Allen wrench (in the mounting bolt) as a lever to angle the pad so the trailing edge is 1mm from the rim.

Check adjustments by reseating the spring and squeezing the lever.

3. Balancing the brake spring tension.

For a firm feel at the lever, and to make sure one pad doesn't drag on the rim as you ride, brakes need to be

centered so that both pads contact the rim at the same time.

Fig 22

Most linear-pull brakes come equipped with spring tension screws. These screws, located at the base of the brake arms, adjust the tension on the brake return springs.

Increasing the tension (turning the screw clockwise) on a particular arm will move that arm further from the rim. Turning the screw counterclockwise will move that arm closer to the rim.

To preserve the overall tension on the brake, you should make adjustments using both screws. For instance, to move the brake to the right, tighten the right screw and loosen the left screw by the same amount.

Fig 23

A good way to check that both pads are contacting at the same time is to give the wheel a spin and squeeze the lever gradually until one of the pads rubs the rim and stops the wheel (hold the lever still as soon as you detect contact).

Then, squeeze the lever further and observe which pad continues to move toward the rim. If the right pad moves, the brake is too far to the right, if the left moves, it’s too far to the left.

4. Lube the cables.

For the brakes to function efficiently, the cables should be lubed where they pass through the cable housing.

Fig 24

Create slack in the cable by disconnecting the brake.

To disconnect the brake, pull the noodle and the cradle apart and lift the noodle out of the slot.

You may have to shove the rubber boot out of the way first (toward the cable cinch bolt).

Fig 25

If you can't pull the cradle and noodle far enough apart to disconnect them, you can create create slack in the cable by loosening the cable anchor bolt, freeing the cable.

Last Updated: 11/20/2006.

Fig 26

Disconnecting the noodle.

Fig 27

Once the brakes are disconnected there should be enough slack to remove the cable housing from the housing stops on the frame.

Slide the housing back out of the stop and lift the cable through the slot in the stop.

Fig 28

Slide the housing along the cable to expose the hidden sections of cable.

Apply a thin coat of oil to the cable (Tri-Flo works well).

Move the housing back into position and reseat the cable, return the noodle to its home, and reattach the cable if necessary. Give the lever a few squeezes to distribute the oil in the housing.

5. Seat the cables.

Before adjusting the brake cable, it's a good idea to give the lever a few squeezes to make sure all cable housing

is fully seated in the cable stops and barrel adjusters.

Fig 29

At this point you should also do a visual inspection to make sure all housing is in place.

Last Updated: 11/20/2006.

6. Set brake cable tension.

The cable tension controls the distance between the brake pads and the rim. A cable that is set too tight will hold

the pads too close to the wheel causing them to rub the rim as you ride. A cable that is too loose results in brakes

that feel "soft" or are ineffective because the lever goes all the way to the handlebar before the brake engages.

Fig 30

First, screw the barrel adjuster on the brake lever all the way in (clockwise). Then back it out one turn (counterclockwise). This will provide room for fine tuning later.

On linear-pull brakes, it's important that there is not too much cable tension to prevent you from being able to

unhook the saddle and open the brakes in the future.

Fig 31

A good way to ensure there is enough slack to unhook the noodle is to adjust the cable tension with the noodle partially unseated.

Pull the noodle and cradle apart as if you were opening the brake, but don't lift it out of the cradle. Hook it against the cradle as shown.

Fig 32

Loosen the brake cable pinch bolt on the brake arm enough to free the cable.

Fig 33

Use one hand to both brace against the brake arm and pull the cable throught the cinch bolt as shown.

Pull the cable through the cinch bolt until the pads contact the rim.

With your other hand, tighten up the cinch bolt.

Reseat the noodle, allowing the pads to move away from the rim, and check the adjustment.

Fig 34

The brakes should engage when the lever has travelled about 1/3 of the way to the handlebar.

Last Updated: 11/20/2006.

Fig 35

At this point, small adjustments can be made with the barrel adjusters (be sure to lock the barrel locknuts to preserve your adjustment settings).

It's important that the barrel adjuster has no more than a few (3 for example) threads exposed. This allows for future adjustability and prevents strip-out.

Any large change in the cable tension should be done by reanchoring the brake cable, not by backing out the barrel adjuster.

7. Final check

Squeeze the levers a few times, make sure they feel good and that both levers engage similarly. Spin the wheel

and look and listen for any rubbing. Take the bike for a ride to test the brakes. They should stop quietly, smoothly,

and effectively.

If your brakes squeal, try giving them some toe-in or increasing the toe-in.

On certain low-end generic brake pad/rim combinations, it may be impossible to eliminate all brake squeal.