How To Reverse Bleed The Brake Systems On Your Dirt Bike

Jul 3, 2019

How To Reverse Bleed, Fill Or Replace The Brake Fluid On Your Dirt Bike.

Bleeding Tools And Supplies:

Pre-Service Notes

Prep your bike by wrapping the brake caliper and reservoir in a towel, and removing the reservoir cap.
Attach your hose to your filling syringe and secure it with a zip tie, then draw in fresh fluid.
All brake systems have different capacities, so fill your syringe with at least 150ccs.
Turn your syringe, so the hose is facing up, let the fluid settle, then push the fluid to the end of the tube.

Attach the end of the hose to the bleeding nipple, and secure with a zip tie.
You will get some air in the line, but that’s ok, you can usually work it back into the syringe.
Loop the base of your syringe with handy wire, then hang it off your bike.
This setup will allow you to fill and skim in one shot.
Before you start to reverse bleed, remove the contents of the reservoir using your second skimming syringe.
Apply some pressure to your syringe, then open the bleeder valve ¼ to ½ turn.
You want to keep a slow, steady pressure on the syringe. Once the fluid starts flowing, keep an eye on your reservoir.
If you are replacing the fluid, skim the old fluid when it reaches ¾ capacity, and continue until fresh fluid reaches the reservoir, then fill and remove a little more just to be safe.
You can see the difference between the old and new brake fluid.
When you are filling a dry system after a brake service, fill the system until the reservoir reaches ¾ capacity, then skim and fill a few more times to ensure all air is purged.
Install the reservoir cap and bladder with overflow, to remove as much air from the reservoir as possible.
Test your brakes, and if everything feels right, pull the tube and wipe your caliper down with brake cleaner.

If you have any questions about brake bleeding, please let me know in the comments or on social.