Q. How do disc brakes work?
A. Brakes rely on friction to slow or stop a car. With disc (rotor style) brakes, the clamping action of the callipers forces brake pads against both sides of the rotor. The resulting friction slows the rotation of the wheel.

Q. Should I worry about brake pulsation (judder)?
A. Yes. In addition to the obvious risks of driving with imperfect brakes, there are important economic considerations as well. Uneven brake wear, the cause of judder, creates 'hot spots' that further damage the disc. Unattended, brake judder worsens to the point where the discs cannot be restored and must be replaced.

Q. What causes brake pulsation?
A. Brake pulsation or judder is the result of uneven wear between brake pads and the disc. In order for a car to stop smoothly, the pad and disc must conform to one another so that brake pressure is consistent over the entire contact area. Minor irregularities in contact will result in 'pedal bounce', while major inconsistencies will cause the entire car to vibrate. In many cases, uneven contact has been caused by lateral runout.

Q. What is lateral runout?
A. On a brake disc, lateral runout is a measurement of how much the surface of the disc wobbles from side to side as it rotates. Lateral runout is usually a result of an eneven disc or slight distortions in the car's hub assembly.

Q. Is it possible to eliminate lateral runout?
A. Yes. By machining the disc to match the hub assembly on which it sits, lateral runout can be eliminated. RMS (Rotor Matching System) technology is the lnly patented system for matching rotors (discs) to hubs.

Q. How does RMS work?
A. With RMS, the brake lathe attaches directly to the hub of the vehicle. This system ensures that the disc is resurfaced true to the hub's axis and thereby guarantees that the hub and the disc are perfectly matched. Off-car bench lathes and other on-car lathes that attach to the brake caliper bracket are not aligned with the hub's axis.

Q. What difference will RMS make?
A. Although any brake lathe will provide a fresh finish on your disc to alleviate brake pulsation, if discs are not matched with your hub brake pulsation will return, - sometimes immediately, and usually within 10,000 miles. By comparison, RMS provides smooth braking for a much longer period, - over 30,000 miles on average.

Q. Will RMS work with the new ABS (Anti-Lock Brake System) or 'trapped' discs?
A. Given the narrower tolerances and higher demands of ABS, it is especially important that theses discs be matched to ensure proper function. For difficult to remove 'trapped' discs (prevalent on many imported cars) RMS allows accurate resurfacing without removing the disc. This means there is less time spent on your car and reduced risk of damage during service.

Q. With all of these advantages, is RMS expensive?
A. No. With the AmD's new brake lathe, faster repair time and fewer chances for mistakes mean larger savings of time and money in the long run.