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7.5 Adjusting Avid BB5 Mechanical Disc Brakes
How Avid BB5 disc brakes work
In order to have a proper understanding of disc brake set up, a full familiarity of the parts that comprise a
disc brake is needed. A mechanical disc brake is made up of a brake lever, a caliper, a cable connecting the
two and a rotor. The caliper, the actual brake bolted to the handcycle, houses two brake pads, inboard and
outboard, between which the rotor will be clamped to provide the braking.
The brake pads sit in the caliper in two orientations. The first, the inboard pad, sits as a fixed/adjustable
pad. It is adjustable during set up, then remains fixed during operation. The second pad, the outboard, is
the moving pad. This pad is attached to an arm on the caliper. This arm contains the cable clamping and
rotates when the brake lever is depressed. This action moves the outboard pad inward toward the inboard
pad, thus clamping the disc rotor.
WARNING:
A brake system that has damage or is not adjusted correctly could decrease your control and
cause you to fall. Make a full inspection of the brakes before each ride. If your brakes do not operate
correctly, do not ride your handcycle. Adjust the brakes or take your handcycle to your dealer for service.
Each month check all the brake bolts, and check the brake pads for worn areas.
Quick and easy adjustment, assuming the rotor, caliper and cable are correctly installed, brake
cable adjustment can be replicated from the V-Brake instructions
1. Loosen the two caliper mounting bolts with a 5mm allen key to a point where the caliper body cam
move freely.
2. Loosen the inboard pad adjustment knob using a Torx T-25 driver.
3. Slide a business card between the outboard, fixed brake pad and the rotor (be sure the card is
between the outboard fixed pad and the rotor, not the inboard adjustable pad and rotor. Then
tighten the pad adjustment knob until the rotor and business card are snugly clamped between the
pads (you should not be able to pull the business card out). This aligns and centres the caliper over
the rotor while leaving a business-card sized gap on the fixed side.
4. With the business card still in place, re-tighten both caliper mounting bolts to lock the caliper in
place.
5. Loosen the pad adjustment knob and remove the business card.
6. Tighten the pad adjustment knob until the pad just barely touches the rotor, and then back off one
click to eliminate pad/rotor contact.
To maintain your mechanical disc brake as your pads wear under normal use, repeat the fine tuning steps
to keep your brakes working great.
