FOR THE DO-IT-YOURSELF DUCATI OWNER

BLEEDING THE BRAKES

$0

11mm End Wrench, 1/4" Clear Tubing, Container, Brake Fluid, WET Rags at the Ready, Phillips Screwdriver

Disclaimer- As with any mechanical adjustment, if done improperly this procedure could be harmful to your bike and could cause severe injury in the event of a crash.  If you are at all unsure of your ability to perform this procedure correctly, PLEASE do not attempt to do so.

What does it mean to "bleed" the brakes? Bleeding the brakes involves draining the air bubbles out of the reservoir, lines and calipers so that only fluid remains.  This is done through a nipple in each of the calipers, and the fluid is expelled out but prevented from going back in, hence the term "bleeding". Air shouldn't be in the system, and makes its way in through leaks in the line, or if the level is low and the bike leans way over, it sucks air.

Why bleed the brakes? It's necessary to bleed the brakes because air in the system decreases braking power or diminishes it completely.  Air compresses more than brake fluid.  When you pull the handle, it compresses the air in the system before it pushes the fluid into the calipers to clamp the rotor, so most if not all of the brake lever travel is wasted and not converted to braking force.  The same goes with the clutch- see my clutch page for info on bleeding your slave cylinder. To start bleeding your brakes, you'll need to slip the tubing over the bleeder nipple on the caliper, and feed it into an empty container.

It's a bit tricky to maneuver into, but you'll need to have one hand on the brake lever, and one hand on the wrench on the bleeder nipple.

Pump once,

twice,

three times, then HOLD CLOSED.

With the brake handle held firmly closed, loosen the bleeder screw.  The pressure at the handle will drop, and fluid will flow into the tube, along with air bubbles no doubt.  Don't be alarmed- just keep the pressure on the handle and continue to force fluid into the tube.  Stop the handle before it reaches the handlebar by closing the bleeder.  The best way to do it is to hold firm pressure on the handle, but only loosen the bleeder a bit, so you have more control over it.

Pump up the handle as shown above between each bleeding.  Also, keep a close eye on the fluid level- it depletes QUICKLY, and if you run out of fluid in the reservoir it will suck air and you'll have to start over.  I'd check after every three bleedings.  As soon as no more bubbles, not not even one, comes out with the fluid, you're done.  Just kink the hose and let the fluid flow to the container, and pop it off.

Then you can top off the fluid and cover it back up.  Be sure to use only DOT 4 or 5.1 fluid.  DOT 3 isn't heavy duty enough, and DOT 5 is a different formula that eats the seals in the master cylinder.  I use 4 because I can't find 5.1 at the local store.  5.1 is better, but 4 works fine for me.

Since I like to fill the fluid to the top to minimize the air in the reservoir, it always flows out when I tighten the lid down.  That's why you need the wet rags handy- brake fluid is terribly corrosive and will damage paint in a matter of minutes.

The rear is a bit trickier because the nipple is on the bottom and it's harder to access.  You could leave the caliper on the bottom and bleed it there.  I have done that and never had a problem.  However, if you consistently have a mushy feel there is probably an air pocket caught in there- to fix this, the manual suggests moving the caliper to the top side of the rotor for a proper bleed, so I have revised my page.

Unbolt the caliper from the mounting bracket.

Once off, you'll need to twist it around so that the line is not kinked, then mount it on top of the rotor.

This is the setup: the caliper on top with a tube leading into a container.  Then you'll mount your 11mm wrench on the nipple, grab the lever, and go to work.

Pump once,

twice,

three times, then HOLD CLOSED.

The same thing as with the front brake- pump it up, hold pressure on the lever, and at the same time realease the bleeder nipple.  Fluid and air will  come out.

Keep pressure on the lever the whole way and when it is about to run out of travel, close the bleeder screw and release the lever.  Then start over with the pumping sequence.  Perform until no more air comes out of the tube with the fluid.

One trick that helps with control is to release the nipple only a slight amount while holding pressure on the lever.  You won't run out of lever travel quickly, and you can make sure you don't run out of fluid in one stroke.  You'll need to press the lever harder, but overall it is a much more controlled action.

You'll have to be even more careful while bleeding the back because the fluid reservoir is smaller and will empty sooner.  Keep a close watch.  When finished, top it off, then wipe off all the surrounding areas with brake fluid on them and close the lid.

Now take the caliper off the top, twist the line back into position, and pry the pads apart with a screwdriver in a gentle motion.  Then mount it back to the bracket to the specified torque (about 25 ft-lbs).

And, you're done.  If you just make sure that you don't let air back into the system, you'll do fine.  When tightening the bleeder screws, DON'T wrench them down, just snug them up tight.  They are easy to strip.  And one more thing- watch where the fluid gets- if at all possible, leave the lids on the reservoirs while bleeding to prevent a jet of fluid from shooting into the air.  Good luck!

This page is in no way associated with Ducati.com, nor is it an entity of Ducati Motor Holding, S.p.A.  All content, information, and views expressed herein are those of myself and do not reflect those of Ducati or its affiliates.  The "DUCATI" logo and "Circle D" are registered trademarks of Ducati Motor Holding, S.p.A., all other content on this website is copyright 2006, Monster Man Productions.  If you would like to link to my page, feel free to do so.

The steps for bleeding are as follows:  you want to pump up the system,
release the bleeder screw while holding pressure on the handle, let some
fluid drain, close the bleeder screw, and release the handle.  You DON'T
want to release the handle at all while the bleeder is open, or air will enter
back into the line and you'll be that much further behind.

Get into position, then perform this sequence:

BEFORE letting go of the lever, close
the bleeder completely.  I can't stress
enough how important it is to never
release the handle even the slightest
amount while the bleeder screw is
loose, because air will get in.  So,
while holding the lever, tighten the
bleeder screw as shown.  Then, you
can repeat this process several times.

Then perform this sequence:

The procedure on a bike with dual discs is the same, except do the one
closest to the master cylinder first, then the opposite one.