Refer to these sections of the Sportsterpedia for recommendations, change intervals and bleeding advice:

• Brake Fluid
• Bleeding the Brake Lines

For more information:

Refer to these threads on the XLForum:

• 2005 Rear Master Cylinder Re-build
• - https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-drivetrain/sportster-motorcycle-tires-wheels-and-brakes-aa/37937-my-rear-master-cylinder-re-build?t=75157
• 2006 vs 2007 1200L Front Brake Caliper
• - https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-drivetrain/sportster-motorcycle-tires-wheels-and-brakes-aa/192254-2007-1200l-front-brake-caliper-question-oddity?threadid=2057183

• Inspect the master cylinder and linkage for damage or leakage, failure to return fully when released, or sponginess when applying pressure.
  • Any problem with the master cylinder requires rebuilding or replacement.
• Brake Fluid Leakage:
  • Any fluid leakage in the brake system should be a signal for replacement of the particular component causing leakage.
  • On an older systems, pay special attention to hoses, looking for cracked or cut surfaces which could develop leakage.
• Check the brake fluid for contamination and proper level.
  • The fluid change level should be 1/8” from top (with reservoir level).
• Perform a stationary test:
  • Squeeze the lever or depress the pedal as hard as possible to make sure the system will not leak or fail.
    Make sure the system releases and the wheel turns freely.
• Linkage inspection: Check for damage and wear especially with non-stock parts.
• Some amount of freeplay must exist in most brake systems.

* . . . Front Master Cylinder Identification

• 1981 and earlier front master cylinders should have some free play.
• 1982 and later do not. The internals are held in place by a seal ring.

• Prior to 2004, there were only two thread pitches for EVO / TC88 models. ¹⁾
  They were 3/8“-24, commonly known as 10mm, and 7/16”-24, commonly known as 12mm.
  (12mm is symbolic only, actual bore size is 11.2mm)
  With the introduction of the 2004 XLH (Sportster) models things changed.
  XL883, XL883C, and XL1200C models use 10mm x 1.25thread on both the front and rear master cylinders and calipers.
  The XL1200R uses a 12mm x 1.5 thread on the front master cylinder and 10mm x 1.25 on the rear master cylinder, and front and rear calipers.
  Only 2004-2006 models use true metric bolts. All other models have not changed.

• Rear Master Cylinder Identification
• Known issues with the 2004-2007 Style Rear Master Cylinder
  
  

• 1982-E1987 master cylinders have aluminum bodies and require a minimum of 1/32” free play.
  They all had a 5/8” bore.

• L1987-2003 master cylinders have built-in free play and use replaceable cartridge type internals that rarely need replacing.
  They all came with a 3/4“ bore.
  The replacement body (42472-87), one piece bore/bowl, is the same part number from L1987-2003.
  

* . . . Rear Brake Caliper Identification

Wrench Sizes & Torque Specs

Caution the use of 6-point sockets and vise-grips will round off the bolt corners. ¹⁷⁾

• Changing pads:
• Caliper to fork mounting bolts (2) (rectangles in pic below):
  • Wrench (10mm 12-point), Torque (28-38 ft/lbs / 38-51.5 Nm). ¹⁸⁾
• Brake Pad Slide Pins (2) (five sided box below):
  • The small bolts on the caliper need to be removed in order to change the pads. ¹⁹⁾
    They will give an audible click when inserted into the housing. ²⁰⁾
  • Wrench (1/4“ 12-point), Torque (180-200 in/lbs / 20.3-22.6 Nm). ²¹⁾
• Bleeder valve:
  • Torque (80-100 in/lbs / 9.0-11.3 Nm) ²²⁾
• Banjo bolt on caliper (six sided box below):
  • Wrench (3/8” 12-point)
• Banjo bolt at M/C:
  • Wrench (7/16 12-point)

• Disassembling the caliper:
• Bridge bolts (2) (rectangles in pic below):
• The 2 larger bolts to the right on the caliper.
  These hold the caliper halves together and shouldn't need to be removed unless you are rebuilding the caliper. ²³⁾
  • Wrench (10mm 12-point), Torque (28-38 ft/lbs / 38.0-51.5 Nm). ²⁴⁾

02 Caliper 25)

Alternative Calipers:

The 2000 and newer bikes have a completely different mounting boss for the brakes. If you want to upgrade to Brembo calipers you're going to need the lowers from a 2000 and newer model. The stock aluminum style is the same price as the chrome version (at retail) so if you like chrome, it's definitely the way to go. ²⁶⁾

When removing the rear caliper pin bolt (44184-04) and raising the caliper, the brake pads will rotate and come out of the retention clip. ²⁷⁾
During reassembly you must be certain to visually check that the brake pads are properly reinserted into the retention clip.
If the pads are not positioned properly you will cross thread the pin bolt in the aluminum caliper during reassembly.
A cross-threaded caliper pin bolt may permit the caliper to rock side to side on the bracket when the brake is applied causing drag and noise.

87-late thru 1999 Brake Pads

Front

Rear

²⁸⁾