Garage Files – Using SRAM’s Bleeding Edge System
Remember when bleeding brakes was the absolute worst maintenance job on a bike? You’d have to break out the plastic squeeze bottles full of carcinogenic chemicals, fashion little catch containers from used Mountain Dew bottles and bent spokes hanging over the handlebars, and even then you weren’t guaranteed that the bleed would work. Unfortunately, what you were guaranteed was a toxic spill of brake fluid on the garage floor and a 50-percent chance of coming away with a squishy brake and contaminated pads. SRAM is looking to solve this issue with its new bleeding system dubbed “Bleeding Edge.” The system uses a nifty quick-release port on the caliper to reduce fluid loss and to streamline a process that used to be the biggest maintenance headache on the planet. The Bleeding Edge is currently only available on SRAM’s Guide Ultimate brakes, but will most likely find its way onto the rest of their brake lines very soon. We show you how the system works in this month’s “Garage Files.”
—A SRAM Bleeding Edge bleed kit (At SRAM.com)
—Torx key set with a T10 bit
—Clean shop rag
—Isopropyl alcohol in a squirt bottle
—Scriber and 2.5-millimeter Allen wrench (not pictured)
1-Start by removing the wheel. Set this in a safe place away from the bleeding action.
2-Remove the E-clip and pad retainer bolt using the scriber and 2.5-millimeter Allen wrench. Then remove the pads through the back of the caliper and set aside.
3-With the pads removed, install the bleeding block like so. This will keep the pistons from migrating in during the bleed process.
4-Fill both syringes with the DOT brake fluid supplied with the SRAM bleed kit. Be sure to only use DOT 5.1 brake fluid with this system. Do not use anything else, as it will destroy your brakes. The syringe with the Edge fitting should be about 1/4 full, and the other one should be about 3/4 full.
5-Turn the pad contact adjustment on the lever all the way out— away from the plus sign—until the knob stops.
6-Use the T10 Torx wrench to remove the bleed screw on the lever. Be sure to put this in a safe place on the bench. It’s small and easy to lose.
7-Attach the non-Edge syringe to the brake lever. Then use the red hose clamp fitting to close off the hose. This will prevent fluid loss later.
8-Remove the rubber bleed cover, and then attach the Bleeding Edge syringe to the caliper like this. The fitting should snap in place relatively easily and will make a satisfying “click” sound when properly fitted.
9-Now, rotate the red Edge knob counterclockwise one full rotation. This will open the bleed port. The fitting came very tight from the factory, so we were forced to use this wrench to break it free at first.
10-Typically, spinning the bleed port open will be easily done by hand.
11-Open the red plastic hose clamp and, with the syringe held vertically, push the fluid through the system. You will see the syringe at the other end begin to fill with fluid. Be sure to stop pushing the fluid before you push the air bubbles in the syringe into the lever.
12-If the fluid that comes out of the brake is discolored, disconnect the system and replace the fluid, then begin the bleeding process again. If the fluid is consistently colored, push the fluid from the bottom syringe back to the top syringe. Again, be sure to stop pushing the fluid before the air bubbles in the syringe make it into the system. Once finished, close the red plastic hose clamp to close the syringe.
13-Pull gently on the plunger of the top syringe to create a vacuum. This will pull some additional air bubbles from the system. Repeat this step a few times until nearly all air bubbles are removed.
14-Finally, gently push down on the plunger to “pressurize” the system. No need to go crazy here. You’re basically only setting the pistons to their correct positions against the bleed block. More pressure is not necessarily better.
15-Close off the hose clamp to prevent excess fluid loss.
16-And then disconnect the top syringe from the brake lever.
17-Replace the bleed screw with the T10 Torx wrench. This is a fairly low torque bolt. Be careful not to over-tighten and strip this out.
18-Use the isopropyl alcohol and clean shop rag to clean the fluid spilled on the lever. There will always be a few drops, no matter how clean and efficient a mechanic you are.
19-Close the Bleeding Edge fitting by tightening it one turn clockwise until it stops. Then, remove the bleed fitting by pulling it straight out of the bleed port.
20-Don’t forget to replace the rubber cover for the bleed port.
21-Thoroughly clean the caliper with the isopropyl alcohol and a clean portion of the rag.
22-Be sure to clean the inside of the caliper, as this area tends to collect spilled fluid and can easily contaminate your pads and rotor. We like this handy “flossing” technique.
23-Replace the pads and spring. We like this “spring sandwich” approach. The pads should slide in from the back of the caliper easily.
24-Replace the pad retainer bolt and E-clip using the 2.5-millimeter Allen wrench. The E-clip will snap on easily by hand.
25-Replace the front wheel, check your handiwork and go hit the trails!
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