ROTOR BEDDING:
All new iron rotors should be bedded-in before being used under racing conditions. Proper bedding-in will prepare the rotor surface, prolong the rotor's life and make it more resistant to thermal checking or cracking under severe braking conditions. The following procedures should be followed when bedding-in rotors:

•Thoroughly inspect all brake system components before proceeding to track. Check all bolt connections, make sure mounting bolts and rotor bolts are properly lockwired, that brake pads are properly secured by retaining clips or cotter pins, that master cylinders and brake pedals are working properly, that brakes are properly bled with plenty of fluid, and that proper engagement of brakes occur when pedal is depressed.

•Because the bedding process is different for rotors and pads, it is best to bed-in a new rotor (disc) using a used set of pads, preferably ones which will not create heat rapidly. Generating heat too quickly will thermal shock the rotors. Likewise, when bedding-in a new set of brake pads, use a used rotor. This new-used bedding process permits controlled bedding of each individual component.

•Make sure that the rotor surfaces are free from oils, grease and brake fluid.

•Close air ducts approximately 75% to expedite the bedding-in process.

•Run vehicle up to moderate speed and make several medium deceleration stops to heat up the rotor slowly. This will help reduce the chance of thermal shock caused by un-even heating of the rotor.

•Pull into the pits and allow the rotor to cool to ambient air temperature.

•Do not hold brakes on after performing the bedding-in procedure until cooling is completed. This will avoid “hot spotting” or un-even cooling which can damage the rotor.

ROTOR RUNOUT:
Rotor runout should be adjusted as soon as you receive your Wilwood components. Wilwood rotors are precision machined to ensure the rotor surfaces are flat and parallel. Sometimes hubs, bearings or other components have runout that cause the rotor to runout. As a rule of thumb, allowable runout should be .005” - .008”. Adjust the runout by re-indexing the rotor or by placing shims between the rotor and hub, or hat. Runout should be rechecked regularly. You can assume the runout to be acceptable as long as you are not experiencing brake drag, pedal oscillation or excessive piston knock back.

ROTOR WEAR:
Rotors will eventually start to show signs of wear; how fast depends on the type of racing, the frequency, and the brake usage. Grooving and/or cracking due to severe heat and thermal cycling indicate the rotor should be replaced. Note that surface checking itself is not a sign a rotor needs replacing as this can occur on iron rotors. Always replace rotor mounting bolts and lockwire whenever replacing rotors, taking care to inspect mounting hats or hubs for signs of abuse.

WILWOOD PRE-BEDDING SERVICE:
Wilwood offers many of their rotors “PRE-BEDDED” at the factory utilizing a computerized brake dynamometer that ensures a consistent “bed” from rotor to rotor. This yields “ready-to-race” rotors, which eliminates valuable practice laps when time is at a premium.

Please contact your Wilwood representative for price and availability.