1100rt brake bleed question

[propinquitous]

Hi everyone, my first post so hoping im doing everything correctly.

 

When replacing the brake lines, is the refill procedure the same as with a basic fluid flush, or do I need to do the ABS unit as well since there's no fluid in the master cylinder? I'm hoping I don't have to remove the tank again, not long had it off to do the HES.

 

Thank you

[dirtrider]

21 minutes ago, propinquitous said:

Hi everyone, my first post so hoping im doing everything correctly.

 

When replacing the brake lines, is the refill procedure the same as with a basic fluid flush, or do I need to do the ABS unit as well since there's no fluid in the master cylinder? I'm hoping I don't have to remove the tank again, not long had it off to do the HES.

 

Thank you

Morning  propinquitous

 

If the master cylinder & lines/hoses are drained of fluid then you will have a little air trapped in the ABS pump after bleeding. Not a lot but some trapped in the ABS pump dome. 

 

So you really should move the fuel tank then bleed the ABS pump if you want all the air removed.

 

If you haven't taken it apart yet then you can try a cheat, that is to open a bleed screw on a front caliper slightly (then with drain hose on the bleed screw) slowly pull the brake lever until it contacts the handlebar.   Then zip tie it to the pulled lever to the hand grip. This closes off the master cylinder fluid intake port so the front master cylinder reservoir doesn't drain. In most cases this will prevent air entry into the ABS pump during system bleeding.

 

Then do the same for the rear, open a bleed screw on the rear caliper slightly (then with drain hose on the bleed screw) slowly push the brake pedal all the way down.   Then tie down or hang a weight on the rear brake pedal to hold it down. This closes off the master cylinder fluid intake port so the rear master cylinder reservoir doesn't drain. In most cases this will prevent air entry into the ABS pump during system bleeding.

 

Not 100% but if done correctly it can pretty well prevent air entry into the ABS pump. Just make darn sure the front or rear reservoirs never get low enough to become empty at any time.

 

If you are replacing the upper front brake hose (between master cylinder & frame) then the above won't work as that will still allow air to get into the ABS system.

[propinquitous]

14 minutes ago, dirtrider said:

Morning  propinquitous

 

If the master cylinder & lines/hoses are drained of fluid then you will have a little air trapped in the ABS pump after bleeding. Not a lot but some trapped in the ABS pump dome. 

 

So you really should move the fuel tank then bleed the ABS pump if you want all the air removed.

 

If you haven't taken it apart yet then you can try a cheat, that is to open a bleed screw on a front caliper slightly (then with drain hose on the bleed screw) slowly pull the brake lever until it contacts the handlebar.   Then zip tie it to the pulled lever to the hand grip. This closes off the master cylinder fluid intake port so the front master cylinder reservoir doesn't drain. In most cases this will prevent air entry into the ABS pump during system bleeding.

 

Then do the same for the rear, open a bleed screw on the rear caliper slightly (then with drain hose on the bleed screw) slowly push the brake pedal all the way down.   Then tie down or hang a weight on the rear brake pedal to hold it down. This closes off the master cylinder fluid intake port so the rear master cylinder reservoir doesn't drain. In most cases this will prevent air entry into the ABS pump during system bleeding.

 

Not 100% but if done correctly it can pretty well prevent air entry into the ABS pump. 

 

If you are replacing the upper front brake hose then the above won't work as that will still allow air to get into the ABS system.

Thank you, I should have asked sooner it seems as I've already got an empty master cylinder! Looks like I'll have to bleed the ABS unit then. Not to worry, good practice getting all the tupperware off I suppose!

[Dave P]

Prop- when I put new hoses on my 1100RT about 5 years ago, I bled the abs block and got horrible dark fluid out of her. Probably original juice! I think you will be glad you bled the abs block. Dave

[wbw6cos]

It probably cannot hurt to excercise the ABS function ervery once in a while.  

[Michaelr11]

propinquitous

 

Your more difficult issue will be the rear brake line, in my experience.  The rear line has the ABS pump as the highest point.  Once you open the line to the rear caliper, air will get into that circuit.  Since the ABS is the highest spot, it is difficult to get the circuit to pump fluid UP to the ABS.  My experience is that you will need to get vacuum on the rear circuit in order to pull fluid UP from the rear master cylinder to the ABS, then down to the caliper.  You could try to back fill by pushing brake fluid from the rear caliper up to the ABS and then it will start flowing into the rear reservior. I have had that work most of the time.

 

The front circuit, the reservior on the handle bar is the highest spot and it will fill the entire circuit with just gravity feed and some gentle pumps on the front lever. After you get fluid down at the caliper and bleed like normal, you should get a firm lever response.  Pull the lever so it is firm and then hold it there, then tie it with string or rubber bands and leave it under pressure over night. That should get any trapped air out.  You could "burp" the ABS bleeder whenever you next have the tank off, or the tupperware off and just lift the tank enough to get at it. 

[propinquitous]

42 minutes ago, Michaelr11 said:

propinquitous

 

Your more difficult issue will be the rear brake line, in my experience.  The rear line has the ABS pump as the highest point.  Once you open the line to the rear caliper, air will get into that circuit.  Since the ABS is the highest spot, it is difficult to get the circuit to pump fluid UP to the ABS.  My experience is that you will need to get vacuum on the rear circuit in order to pull fluid UP from the rear master cylinder to the ABS, then down to the caliper.  You could try to back fill by pushing brake fluid from the rear caliper up to the ABS and then it will start flowing into the rear reservior. I have had that work most of the time.

 

The front circuit, the reservior on the handle bar is the highest spot and it will fill the entire circuit with just gravity feed and some gentle pumps on the front lever. After you get fluid down at the caliper and bleed like normal, you should get a firm lever response.  Pull the lever so it is firm and then hold it there, then tie it with string or rubber bands and leave it under pressure over night. That should get any trapped air out.  You could "burp" the ABS bleeder whenever you next have the tank off, or the tupperware off and just lift the tank enough to get at it. 

Thank you for the concise reply. In regards to the front lines and the ABS unit, I would just undo the nipple on the ABS unit after ive got the calipers sorted, and connect the hose to it the same way I do on the calipers, and pump the front brake lever? Or is there a different way I'm supposed to do it?

[propinquitous]

1 hour ago, Dave P said:

Prop- when I put new hoses on my 1100RT about 5 years ago, I bled the abs block and got horrible dark fluid out of her. Probably original juice! I think you will be glad you bled the abs block. Dave

Quite possibly i will have the same. The fuel filter was from 1998 when I changed that, and I think the plugs were original too. 

[dirtrider]

28 minutes ago, propinquitous said:

Thank you for the concise reply. In regards to the front lines and the ABS unit, I would just undo the nipple on the ABS unit after ive got the calipers sorted, and connect the hose to it the same way I do on the calipers, and pump the front brake lever? Or is there a different way I'm supposed to do it?

Evening propinquitous

 

I haven't ever had any issues getting rear fluid flow to & through the ABS pump. The secret is to bench bleed the rear master cylinder before trying to bleed the entire rear brake circuit. 

 

What happens is: if the rear master cylinder isn't bench bled (pre-bled) then the cylinder & lines are full of air, every time the pedal is pushed all it pumps is air. That air compresses enough that it just won't pump fluid through the system.

 

By pre-bleeding the rear master cylinder it then pumps a full cylinder of fluid & that full cylinder (full stroke) is just enough to get the fluid up & through the ABS pump. 

 

Bench bleeding (pre-bleeding) also helps the front bleed easier as it doesn't have to pump all that air through the system before it starts pumping actual fluid.

 

To bench bleed (pre-bleed) you don't actually have to remove the master cylinder & place it on the bench.  You just need to fill the reservoir, then work the foot pedal lightly (just depress the pedal about 1/8 to 1/4 travel, no more). Do this a number of times until air bubbles quit coming up into the reservoir). This allows the trapped air in the master cylinder bore to come back up & out of the bore through the take-up port. Once you get the air out of the master cylinder it will then pump a full cylinder of fluid on every full travel pedal pump. 

 

One I get the air out of the master cylinder I put a hose on the open caliper bleeder, then terminate that hose in a bottle or jar with  enough brake fluid in the bottom to have the hose end terminate below the fluid level (THIS then acts as a check valve when pumping the brake pedal). I just leave the caliper bleeder open then pump the heck out of the pedal. It usually doesn't take many pumps to get the fluid flowing. 

 

On the front, just toss a (clean) box cutter blade or quarter in the bottom of the reservoir while bleeding as that prevents fluid squirting up through the take-up port hole & onto the motorcycle.    

 

Also, brake fluid is very harmful to paint & plastic so cover the dash & painted surfaces around the master cylinder with plastic garbage bags before bleeding the system. Caution, DO NOT GET ANY brake fluid on dash plastic or pained surfaces.

 

 

 

 

[Michaelr11]

3 hours ago, propinquitous said:

Thank you for the concise reply. In regards to the front lines and the ABS unit, I would just undo the nipple on the ABS unit after ive got the calipers sorted, and connect the hose to it the same way I do on the calipers, and pump the front brake lever? Or is there a different way I'm supposed to do it?

Yes.  Keep in mind that on the ABS2 system on the 1100RT , the fluid runs from end to end, passing through the ABS module . Once you have the initial bleeding done, the bleeding needed to get to new fluid at the ABS bleed nipple is tiny. When I do bleed the module, all I do is attach a clear tube to the nipple, put a little pressure on the lever, and crack open the bleed valve for about an inch of fluid to enter the tube.  If your system hasn’t been bled in years, you may have to allow a little more fluid to bleed out.

 

DR brings up a process for starting the rear brake bleed that I have never tried. I appreciate that info, and will try it if I have any time that I lose fluid in the rear circuit.

 

[Redfoxx]

7 hours ago, Dave P said:

Prop- when I put new hoses on my 1100RT about 5 years ago, I bled the abs block and got horrible dark fluid out of her. Probably original juice! I think you will be glad you bled the abs block. Dave

I just replaced lines on a 2004 1150rt I just  purchased, When I bleed ABS it sounds like yours I had brown looking fluid coming out. I also had dark fluid from front left caliper and some black floating goop.  I am guessing mine had either 10 years or 20 years on fluid, it was serviced by dealer 10 years ago and it said brakes in owners manual. So I would say 10 years is way to long. 

[propinquitous]

7 hours ago, dirtrider said:

Evening propinquitous

 

I haven't ever had any issues getting rear fluid flow to & through the ABS pump. The secret is to bench bleed the rear master cylinder before trying to bleed the entire rear brake circuit. 

 

What happens is: if the rear master cylinder isn't bench bled (pre-bled) then the cylinder & lines are full of air, every time the pedal is pushed all it pumps is air. That air compresses enough that it just won't pump fluid through the system.

 

By pre-bleeding the rear master cylinder it then pumps a full cylinder of fluid & that full cylinder (full stroke) is just enough to get the fluid up & through the ABS pump. 

 

Bench bleeding (pre-bleeding) also helps the front bleed easier as it doesn't have to pump all that air through the system before it starts pumping actual fluid.

 

To bench bleed (pre-bleed) you don't actually have to remove the master cylinder & place it on the bench.  You just need to fill the reservoir, then work the foot pedal lightly (just depress the pedal about 1/8 to 1/4 travel, no more). Do this a number of times until air bubbles quit coming up into the reservoir). This allows the trapped air in the master cylinder bore to come back up & out of the bore through the take-up port. Once you get the air out of the master cylinder it will then pump a full cylinder of fluid on every full travel pedal pump. 

 

One I get the air out of the master cylinder I put a hose on the open caliper bleeder, then terminate that hose in a bottle or jar with  enough brake fluid in the bottom to have the hose end terminate below the fluid level (THIS then acts as a check valve when pumping the brake pedal). I just leave the caliper bleeder open then pump the heck out of the pedal. It usually doesn't take many pumps to get the fluid flowing. 

 

On the front, just toss a (clean) box cutter blade or quarter in the bottom of the reservoir while bleeding as that prevents fluid squirting up through the take-up port hole & onto the motorcycle.    

 

Also, brake fluid is very harmful to paint & plastic so cover the dash & painted surfaces around the master cylinder with plastic garbage bags before bleeding the system. Caution, DO NOT GET ANY brake fluid on dash plastic or pained surfaces.

 

 

 

 

Good tip about the box cutter blade, I'll be using that for sure. Thank you.

[propinquitous]

4 hours ago, Michaelr11 said:

Yes.  Keep in mind that on the ABS2 system on the 1100RT , the fluid runs from end to end, passing through the ABS module . Once you have the initial bleeding done, the bleeding needed to get to new fluid at the ABS bleed nipple is tiny. When I do bleed the module, all I do is attach a clear tube to the nipple, put a little pressure on the lever, and crack open the bleed valve for about an inch of fluid to enter the tube.  If your system hasn’t been bled in years, you may have to allow a little more fluid to bleed out.

 

DR brings up a process for starting the rear brake bleed that I have never tried. I appreciate that info, and will try it if I have any time that I lose fluid in the rear circuit.

 

That's brilliant, thank you. I would surely have bled much more than that as I wouldn't have assumed the amount in the unit was that small. Doesn't sound so bad after all.

[dirtrider]

5 hours ago, propinquitous said:

That's brilliant, thank you. I would surely have bled much more than that as I wouldn't have assumed the amount in the unit was that small. Doesn't sound so bad after all.

Moring propinquitous

 

The amount of fluid in the 1100 ABS unit isn't that small. Because of the displacement pistons the ABS-2 holds a fair amount of fluid. 

 

But seeing as the ABS-2 unit is a pass-through unit then most of the internal fluid is bled through when bleeding from master cylinder to caliper or calipers. So just general bleeding, master cylinder to calipers, gets majority of the old fluid & air out. 

 

There is just that little bit of old fluid and/or air that is in the top of the ABS unit that doesn't come out with a general bleed/flush. 

 

That little bit of trapped old fluid (or air if the system was emptied)  is what you get out when bleeding at the ABS unit. 

 

 

[propinquitous]

26 minutes ago, dirtrider said:

Moring propinquitous

 

The amount of fluid in the 1100 ABS unit isn't that small. Because of the displacement pistons the ABS-2 holds a fair amount of fluid. 

 

But seeing as the ABS-2 unit is a pass-through unit then most of the internal fluid is bled through when bleeding from master cylinder to caliper or calipers. So just general bleeding, master cylinder to calipers, gets majority of the old fluid & air out. 

 

There is just that little bit of old fluid and/or air that is in the top of the ABS unit that doesn't come out with a general bleed/flush. 

 

That little bit of trapped old fluid (or air if the system was emptied)  is what you get out when bleeding at the ABS unit. 

 

 

Morning dirtrider, so how important is it to get out? I've bled the brakes before and didn't do this and didn't notice an issue.

[dirtrider]

13 minutes ago, propinquitous said:

Morning dirtrider, so how important is it to get out? I've bled the brakes before and didn't do this and didn't notice an issue.

Morning propinquitous

 

Depends, a little dirty fluid probably won't hurt anything as it will eventually work it's way into the system fluid then come out at next brake fluid service. If you have totally drained the system for hose replacement  then probably no dirty fluid remaining in the ABS unit (or won't be after bleeding anyhow) so that is not a big concern but with a total system drain you will probably have a little air trapped in the ABS unit. 

 

But just because you bled before doesn't mean much now as you have drained the system so this time there is probably a little air trapped in the ABS pump dome.  Even with that trapped air the brakes will still work, might be a little mushy feeling or you might not even notice it.

 

That trapped air could effect ABS operation in some ABS events so really should be bled out at the ABS pump.

 

If you regularly ride hard enough to get the ABS system to go into ABS mode then that air will more than likely eventually work it's way into the master cylinder then into the fluid reservoir (front brake).  But  on the rear brake it will probably stay high up in the ABS pump as both the master cylinder & caliper are well below the top of the ABS unit. 

 

 

 

 

[propinquitous]

42 minutes ago, dirtrider said:

Morning propinquitous

 

Depends, a little dirty fluid probably won't hurt anything as it will eventually work it's way into the system fluid then come out at next brake fluid service. If you have totally drained the system for hose replacement  then probably no dirty fluid remaining in the ABS unit (or won't be after bleeding anyhow) so that is not a big concern but with a total system drain you will probably have a little air trapped in the ABS unit. 

 

But just because you bled before doesn't mean much now as you have drained the system so this time there is probably a little air trapped in the ABS pump dome.  Even with that trapped air the brakes will still work, might be a little mushy feeling or you might not even notice it.

 

That trapped air could effect ABS operation in some ABS events so really should be bled out at the ABS pump.

 

If you regularly ride hard enough to get the ABS system to go into ABS mode then that air will more than likely eventually work it's way into the master cylinder then into the fluid reservoir (front brake).  But  on the rear brake it will probably stay high up in the ABS pump as both the master cylinder & caliper are well below the top of the ABS unit. 

 

 

 

 

Thank you again for taking the time to respond dirtrider.