Welcome to SRAM Technical Communication. Today we'll be guiding you through the bleed procedure for Avid Elixir brakes.
Materials and Tools
Let's get started by taking a look at the materials and tools you'll need in order to complete this service procedure.
Safety glasses and nitrile gloves. An Avid Bleed Kit and a T10 Torx. For clean up you'll need water or isopropyl alcohol and a lint free rag.
When bleeding brakes you may notice discolouration of the old fluid as it exits the system into the syringe at the lever. If the fluid is severely discoloured this indicates that the fluid is very old. In this case bleeding the system twice in order to completely remove the old fluid is recommended.
Bike and Materials Preparation
Before you get started, make sure that the bike is orientated so that the brake lever is higher than the brake caliper.
Fill one syringe one half full of Avid brake fluid, and the other syringe one quarter full.
Hold each syringe with the tip pointed up and tap the side of the syringe with your finger to bring and air bubbles to the top.
Place a towel around the tip and slowly push the air bubbles our of the syringe. Close each hose clamp and pull on the plunger. Bubbles will appear to form and enlarge. Continue to pull on the plunger and lightly tap the syringe to release the bubbles sticking to the sides and the bottom so that they can rise to the top of the fluid.
When the bubbles have stopped forming and have all risen to the top release the plunger, open the clamp and carefully push the air out. Repeat this process several times.
Now that the syringes are ready, remove the wheel from the bike. Remove the brake pads from the caliper and insert the appropriate bleed block. This will help prevent system overfill and keep brake fluid from contaminating your brake pads.
Use a T10 Torx to remove the caliper bleed port screw from the banjo bolt on the caliper body. Make sure the fluid in the one half full syringe is pushed all the way to the tip. Then thread it into the caliper bleed port.
For models with pad contact adjust and a fixed bleed port screw, rotate the adjuster in the direction opposite the arrow until it stops. For models with pad contact adjust and a bleed port screw located on the pad contact adjuster, rotate the adjuster in the direction opposite the arrow until it stops, then rotate the adjuster back just enough to place the bleed screw at its highest point.
Bleed the Hose
Use a T10 Torx to remove the lever bleed port screw. Make sure the fluid in the other syringe is pushed all the way to the tip with no air gap then thread it into the lever bleed port. A small amount of brake fluid may drip from the bleed port screw, this is normal.
Hold both syringes upright. Gently push on the caliper syringe plunger to move fluid from the caliper syringe, through the system and into the lever syringe until the lever syringe has increased to one half full and the caliper syringe has decreased to one quarter full. You should also see air bubbles fill the lever syringe.
Bleed the Caliper
Close the clamp on the lever syringe. Pull the brake lever to the handlebar and fasten it with a toe-strap or rubber bands.
Pull out on the caliper syringe plunger to create a vacuum. The gently push in on the plunger to pressurise the system. Repeat this procedure several times until large bubbles stop coming out of the caliper. Be careful not to pull out too hard on the plunger or you will pull air past the plunger seal.
Once the large bubbles at the caliper have stopped. Remove the toe-strap or rubber bands from the brake lever, but keep the lever pulled in with your finger. While keeping pressure on the brake lever apply pressure on the syringe plunger and allow the brake lever to slowly release to the fully extended position.
Remove the syringe from the caliper and reinstall the bleed port screw. Use a lint-free rag to immediately wipe off any excess fluid.
Bleed the Lever
Open the clamp on the lever syringe. Pull on the lever syringe plunger to create a vacuum. Then gently push in on the plunger to pressurise the system. Squeeze and release the brake lever ten times, allowing the lever to snap back. Repeat this procedure several times until large bubbles stop coming out of the lever. Be careful not to pull out too hard on the plunger or you will pull air past the plunger seal.
Once the large bubbles at the lever have stopped push then release the plunger one last time. Remove the syringe and reinstall the bleed port screw. Use a lint-free rag to immediately wipe off any excess fluid.
Spray isopropyl alcohol or water onto the lint-free rag and wipe off the brake lever and caliper to remove any excess brake fluid you may have missed before.
Remove the bleed block from the caliper and reinstall the brake pads. Reinstall your wheel according to the manufacturer's instructions.
Empty the syringes in to a sealed container and dispose of the fluid properly. Used brake fluid should be recycled or disposed of in accordance to local and federal regulations.
Test the System
Pull on the lever very firmly several times. Make sure to look around the hose nut on the lever and the banjo bolt on the caliper for any leaks. Make on last check of all the bolts and fittings.
This completes the Avid Elixir brake bleed procedure.