Joined Jun 2007
811 Posts | 0+
Nantwich
I have never seen a hydraulic system that allowed outside air into the system without leaking fluid. I know that some believe that the problems with the clutch on the 04's might be caused by the rubber boot gulping air and forcing it into the system.
So, on the Mille you need a piece of vinyl tubing that fits the bleeder. Put one end on the bleeder after your box end wrench and run the other end into a jar. Fill the reservoir. Remember, speed is good and only push the pedal down when the bleeder is open. Open the bleeder. Push the pedal all the way down. Close the bleeder. Let the pedal up. Open the bleeder. Pedal down. Close bleeder. Pedal up. Open bleeder. Pedal down. Close bleeder. Pedal up. Repeat this as quickly and smoothly as you can till the reservoir is almost empty and top up. Continue until you see no bubbles.
Before you can proceed as stated above you must position the caliper correctly. I found that to really get all the air out you need to hold the caliper in two different positions as pictured below. The first is to flush the air out of the gallery in the caliper that distributes fluid from the banjo fitting to both sides of the caliper and the second flushes the air out of the piston bores. You also need to be sure there no high spots in the brake hose where bubbles will collect. I bled mine with both pistons pushed all the way into the caliper. I didn't even have anything in between the pads but it's probably better to put something in there. Mine crept out a little but not much because you never push the pedal with the bleeder closed. Bleeding my bike this way I was able to get a solid pedal after filling the reservoir only seven times.
I really hope this can help some of you and forgive me, I really am not interested in disparaging anyones abilities. I'm just trying to share some things I learned the hard way.
Sometimes if the system has been completely open, such as after replacing the supply line and the pressure line or replacing the MC, the MC may need to be primed with the pressure line removed.
Place a large pan or cookie sheet under the MC as this can get messy. Protect all painted surfaces including the wheel. Remove the wheel if you have to. It doesn't hurt to have a hose or spray bottle of water handy just in case.
Remove the banjo bolt securing the pressure line. Fill the reservoir. You're going to use your finger like a check valve. Put your finger over the MC outlet. Push the pedal all the way down allowing any pressure you feel past your finger. Close the opening and let the pedal up. If you feel any suction keep a tight seal till it dissipates. Pedal down, releasing pressure. Pedal up and again keep a tight seal till the suction dissipates. Pretty quickly you will start to get fluid flowing. Repeat till you get a full stroke with no bubbles. Hold the pedal down somehow and reattach the pressure line and tighten.
You can now start bleeding the system as described in the article.
Article kindly used with permission from KZmille (Author)
So, on the Mille you need a piece of vinyl tubing that fits the bleeder. Put one end on the bleeder after your box end wrench and run the other end into a jar. Fill the reservoir. Remember, speed is good and only push the pedal down when the bleeder is open. Open the bleeder. Push the pedal all the way down. Close the bleeder. Let the pedal up. Open the bleeder. Pedal down. Close bleeder. Pedal up. Open bleeder. Pedal down. Close bleeder. Pedal up. Repeat this as quickly and smoothly as you can till the reservoir is almost empty and top up. Continue until you see no bubbles.
Before you can proceed as stated above you must position the caliper correctly. I found that to really get all the air out you need to hold the caliper in two different positions as pictured below. The first is to flush the air out of the gallery in the caliper that distributes fluid from the banjo fitting to both sides of the caliper and the second flushes the air out of the piston bores. You also need to be sure there no high spots in the brake hose where bubbles will collect. I bled mine with both pistons pushed all the way into the caliper. I didn't even have anything in between the pads but it's probably better to put something in there. Mine crept out a little but not much because you never push the pedal with the bleeder closed. Bleeding my bike this way I was able to get a solid pedal after filling the reservoir only seven times.
I really hope this can help some of you and forgive me, I really am not interested in disparaging anyones abilities. I'm just trying to share some things I learned the hard way.
Sometimes if the system has been completely open, such as after replacing the supply line and the pressure line or replacing the MC, the MC may need to be primed with the pressure line removed.
Place a large pan or cookie sheet under the MC as this can get messy. Protect all painted surfaces including the wheel. Remove the wheel if you have to. It doesn't hurt to have a hose or spray bottle of water handy just in case.
Remove the banjo bolt securing the pressure line. Fill the reservoir. You're going to use your finger like a check valve. Put your finger over the MC outlet. Push the pedal all the way down allowing any pressure you feel past your finger. Close the opening and let the pedal up. If you feel any suction keep a tight seal till it dissipates. Pedal down, releasing pressure. Pedal up and again keep a tight seal till the suction dissipates. Pretty quickly you will start to get fluid flowing. Repeat till you get a full stroke with no bubbles. Hold the pedal down somehow and reattach the pressure line and tighten.
You can now start bleeding the system as described in the article.
Article kindly used with permission from KZmille (Author)
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