Hydraulic Brake Bleed (Hub Motor Wheel)

Service Price: $65

A hydraulic disc brake bleed on a wheel that has a hub motor is the same process for a regular hub, with the added labor of having to remove the ebike hub motor from the ebike before being able to bleed the brakes. During our ebike hydraulic disc brake bleed service on a hub driven wheel, the first step we take is to remove the wheel, exposing the disc brake caliper. While we do this, we take care to disconnect the motor from the ebike controller cables. With the caliper exposed, we then remove the ebike disc brake pads from the caliper. This is one of the most important steps because the hydraulic fluid or mineral oil inside of the brake lines can contaminate and ruin the brake pads if it gets on them. So we remove them and set them to the side so they remain clean and reusable. Once the brake pads have been removed from the caliper, we put in a bleed block. A bleed block is just a solid piece of plastic molded to be the perfect size to fit into the caliper. This block prevents the brake calipers from being pushed out of their slots while bleeding the brakes.

With that brake block installed, we can now start bleeding the brakes. To bleed the brakes, we would first attach our Park Tool bleed kit to the reservoir in the ebike brake lever, and then the other to the brake caliper itself. The procedure is a bit different depending on the brakes are being bled, but the basic process is to first push out all of the old hydraulic fluid, while replacing it with new, clean fluid. This is done by pushing the bleed syringe filled with new fluid attached to the caliper. The old fluid can then be seen coming out of the other end at the brake lever with the bleed syringe attached there. Once the fluid coming out of the other begins to look clear and clean again, then the fluid has been properly replaced. We then have to work out any air bubbles that may have gotten into the hydraulic system. To help with this, we usually will rotate the ebike around on our work stand, so the bubbles in the system float up and out of the top of the hydraulic system and into the bleed syringe. Once no more bubbles are coming out, we remove the bleed syringes and close the bleed ports back up on the brake lever and brake caliper. Finally, we reinstall the brake pads and remount the wheel. After remounting the wheel, we then reconnect the ebike hub motor to the controller, while making sure the motor works as it should after being removed. Your ebike brake bleed is now complete and your ebike hydraulic brakes should feel brand new!

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