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Very mechanically inclined here. I have bleed brakes before but all I read is how difficult it is to bleed the brakes on the ABS system. I have the extension kit on order and it means replacing the rear brake line, so I can either do it myself or take it 100 miles to the nearest dealer.

What is the hang up? What makes it so much tougher? I have a vacuum bleeder kit.
 

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Very mechanically inclined here. I have bleed brakes before but all I read is how difficult it is to bleed the brakes on the ABS system. I have the extension kit on order and it means replacing the rear brake line, so I can either do it myself or take it 100 miles to the nearest dealer.

What is the hang up? What makes it so much tougher? I have a vacuum bleeder kit.
I can not stress this enough do not use the vacuum bleeder.
Do it the old school way, have some one pump and hold while someone cracks the bleed.
As long as you do that and don't allow the master cylinder to empty and suck in air you will not have a problem

Sent from my SM-G965U using Tapatalk
 

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I can not stress this enough do not use the vacuum bleeder.
Do it the old school way, have some one pump and hold while someone cracks the bleed.
As long as you do that and don't allow the master cylinder to empty and suck in air you will not have a problem

Sent from my SM-G965U using Tapatalk
That is how I did it. Very simple. If I can do it anybody can.
 

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there's also a thread on here about using bleeder valves that bleed when cracked open but close when pressure is off... one person job... and what's the deal with a vacuum bleeder? I know several guys that use it and never had problems
 

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I bled w/vacuum Friday night... and did a ton of riding this weekend in addition to this morning.
What is going to happen?
 

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I have used the Mityvac vacuum bleeder on all my bikes including my Springfield. Never seemed to be a problem.
What is the issue with using them ?
 

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Not much of an explanation as to why a vacuum bleeder is such a bad idea. Inquiring minds want to know. Auto mechanics use vacuum bleeders all day long. Is the motorcycle ABS system significantly different? If you know something more please share. That's what we are interested in.
This article goes into actually using the dealer service tool to actuate the ABS to get ALL of the old brake fluid. But still says:
"In general, whenever you are bleeding an ABS-equipped vehicle you can do so exactly as you would any other vehicle - stroke the pedal to pressurize the system, open a bleeder, close the same bleeder, and repeat. This does not change whether you are pressure-bleeding, vacuum-bleeding, or manual-bleeding. Just follow the same steps you normally would for a non-ABS vehicle and you're most of the way there. "
 

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Didn't look into it.
I'm way too busy at my shop to investigate every little thing. That happens in the down season.
I'm telling from experience from the hundreds of Indians that i have bleed.
Everyone done w a vacuum cam out spongy. It doesn't take long to bleed them the old school way
Vacuum bleeder is banned from my shop.

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We use the vacuum to empty most of the brake fluid from the wells just above the holes so no air can get in. Then one pumps pulling the brake fluid and one pours to keep the well full. No, we are not a shop where money is counted we do our own maintenance.
 

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Something additional to think about if running ABS. Bleeding them is fine but after you complete that and out on a test run....initiate the ABS on both front and back. This moves the solenoids and gives them a work out. Keeps them from eventually freezing up. Seeing that on some of the older bikes (non-Indian) that use ABS. Also see that on cars as well. Changing out that brake fluid is the best thing you can do on a periodic basis to keep the brake system functional.
 

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...Auto mechanics use vacuum bleeders all day long. Is the motorcycle ABS system significantly different? If you know something more please share. That's what we are interested in.
...
BMW and Mercedes shop I worked in (nearly 20 years ago), we were required to use a pressure bleeder (connects up at the master cylinder, fills with pressurized brake fluid, makes a huge mess if you don't get it sealed correctly).
The only thing I understood was that pulling a vacuum could allow air bubbles to form/remain in the system. There's a few possibilities of how that happens. Using the pressure bleeder, always got good results.
Cycling the ABS is(was) to get the old fluid out of the ABS pump. Ask around your area and find out how many actually do that step.
 

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BMW and Mercedes shop I worked in (nearly 20 years ago), we were required to use a pressure bleeder (connects up at the master cylinder, fills with pressurized brake fluid, makes a huge mess if you don't get it sealed correctly).
The only thing I understood was that pulling a vacuum could allow air bubbles to form/remain in the system. There's a few possibilities of how that happens. Using the pressure bleeder, always got good results.
Cycling the ABS is(was) to get the old fluid out of the ABS pump. Ask around your area and find out how many actually do that step.
i guess i can concede on the "why", and I am inclined to believe this since thomasjt579 has seen it multiple times in his shop, but still hung up on "how". Brake system is sealed, and if one doesn't let the reservoir get too low on fluid, how would air get into the system? A vacuum is negative pressure to pull the fluid through the system, and using the hand pump the lever process is positive pressure in the system to push fluid out. Still cant understand how negative pressure will introduce air, or spongy results when positive pressure does not. Not questioning anyone's real world results, just interested in the science of it all.
 

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I don't see how air enters a complete brake system if the vacuum setup is done correctly. One way would be if you let the level fall too low in the master cylinder then air will get sucked in. Second, the system has a leak which someone should notice long before bleeding the brakes.

So if the system is good..no leaks and the level does not fall too low then no air will enter the system.
 

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I don't see how air enters a complete brake system if the vacuum setup is done correctly. One way would be if you let the level fall too low in the master cylinder then air will get sucked in. Second, the system has a leak which someone should notice long before bleeding the brakes.

So if the system is good..no leaks and the level does not fall too low then no air will enter the system.
Answering both questions, on a low level, in one shot:

There are instances where a system doesn't leak under positive pressure (normal operation), but does under negative pressure. There is also the introduction of oxygen under negative pressure, the Bens(?) Ask a scuba diver. Or a pilot. I had a friend that was surprised when I said his rear brake didn't work on his KTM. Trick was, I was using low pressure on the rear brake and it was bleeding through (I think through a backwards installed cup seal) when I went over whoops. Properly installed, great under pressure, but when backwards and pressurized at low levels, it leaked leading to brake failure.

Lastly, if there is a problem hidden in the system, the best bleeding practice hides it and routine methods to discover it are unsuccessful.
 

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Answering both questions, on a low level, in one shot:

There are instances where a system doesn't leak under positive pressure (normal operation), but does under negative pressure. There is also the introduction of oxygen under negative pressure, the Bens(?) Ask a scuba diver. Or a pilot.
Lastly, if there is a problem hidden in the system, the best bleeding practice hides it and routine methods to discover it are unsuccessful.
I just happen to be a scuba diver, a Divemaster actually, (and if any of you have never been, I highly recommend the experience if you get the chance). I think you are referring to "The Bends" where when you dive down the air in your tanks compress and you are breathing in that compressed air. The issue isn't with oxygen in the air tank, but with the nitrogen in your air tank. On the way up to the surface that compressed air is decompressing in your blood stream and the nitrogen bubbles get bigger, and if you come up too fast they get caught in your joints which makes them get stuck in the bent position, hence "the bends".
I am still not sure how negative pressure can introduce oxygen in the brake system, but it does make some sense that negative pressure (abnormal operation) could exploit a weakness in the system, even if the weakness never will show up under normal operation. Since vacuum bleeder are OK in most systems, but not in the Indian systems, does that mean there is something not quite right with these brake systems?
 
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