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Discussion Starter #1
Getting ready to flush the brake fluid and bleed the brakes again on my 01. Last fall while in California I noticed a slight chatter. It only happened during one ride, and hasn't happened since, however the brake pedal has always been soft....... Very soft.

I know about the bleeding of the "L" shaped block on the upper left frame near the steering head, and will be bleeding that. But my question is, whats the reason / importance of the sequence in the brake bleeding?? Last year when I bled them I followed the directions to the "T", with the exception of the "L" shaped block, and it didn't seem to make any difference to the rear pedal at all. I achieved a fluid change, but not much else. So whats the reasoning for the Bleeding sequence??
 

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Sometimes you can fix a soft pedal by tieing the pedal down and leave it overnite or for several hours.
I don't think the above will help anything. However, the reason for the sequence is so that the old fluid and any debris will be flushed out using the least amount of brakefluid possible. If you do it in a different sequence you may have to go back and reflush because of the linked braking system. That little fitting on the upper left side of the frame traps air and that is what give you the soft rear pedal as well as the chatter when it is hot. The chatter doesn't seem to happen when things are cold. Rocky used to post the sequence that included the fitting and that procedure worked well for me.
 

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I don't think the above will help anything. However, the reason for the sequence is so that the old fluid and any debris will be flushed out using the least amount of brakefluid possible. If you do it in a different sequence you may have to go back and reflush because of the linked braking system. That little fitting on the upper left side of the frame traps air and that is what give you the soft rear pedal as well as the chatter when it is hot. The chatter doesn't seem to happen when things are cold. Rocky used to post the sequence that included the fitting and that procedure worked well for me.
So where did it fit in the sequence?
thecruiser
 

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Posted by glarson3:
Make sure you followed all of these instructions:
BRAKE BLEEDING SEQUENCE
1: Front Right Brake Upper Bleeder Valve
2: Front Left Brake Middle/lower Bleeder Valve
Rear Reservoir (under right side chrome engine cover)
1: Front Left Brake Upper Bleeder Valve
2: Front Right Brake Lower Bleeder Valve
3: Rear Brake Lower Bleeder Valve
4: Anti-Dive: bleeder valve on top
5: Rear Brake Upper Bleeder Valve


Do these two additional Steps to be sure you have no residual air bubble
in the rear system!!
6: Pressure bleeding the lower Junction block. (Upper left side of frame
sitting on bike).Follow rubber hose from Secondary master cyl to the
Junction block.
7) Pressure Bleed the top Banjo bolt on the Secondary Master Cyl. (To be sure
the air bubble is completely out)
 

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Discussion Starter #6
I don't think the above will help anything. However, the reason for the sequence is so that the old fluid and any debris will be flushed out using the least amount of brakefluid possible. If you do it in a different sequence you may have to go back and reflush because of the linked braking system. That little fitting on the upper left side of the frame traps air and that is what give you the soft rear pedal as well as the chatter when it is hot. The chatter doesn't seem to happen when things are cold. Rocky used to post the sequence that included the fitting and that procedure worked well for me.
Thanks! That makes perfect sense.

I have done this once and followed the sequence to the letter, with the exception of the upper block, and found it confusing, and using a Mity Vac, difficult. I have since ordered speed bleeders and will be installing them first!
 

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Sometimes you can fix a soft pedal by tieing the pedal down and leave it overnite or for several hours.
Let me preface this by saying that this is not to be considered a sarcastic or smart elic remark but rather a curious question. I have read on this forum and others that weighing the pedal down helps. With brake bleeding experience for over 40 years on all types of vehicles, please explain to me how this method works. Trapped air bubbles just don't go away overnight, they may collect at one end of the line due to the pedal being weighed down, but the air can not escape the system unless a line or bleeder screw is loosened. I'm not saying it doesn't work because I will not go there. I'm only saying, I don't see how it works since the air is obviously still in the line. And, if your second depression of the pedal is not hard, then that's proof that the air is still there. The first depression will be slightly longer due to the initial fluid needed to move the pads against the rotors and the second will be less and firmer because of less fluid needed due to less travel of the pistons. Now I might add this little note. I once thought I still had air in my lines after bleeding them carefully and completely with certainty that all air was gone. Come to find out, if the front calipers are not positioned correctly over the rotors, you will get that "air in line sensation". This is because the pads are actually making the rotor bend slightly to one side. This can be observed by watching the rotor bend with someone squeezing the front brake lever. If any of you have that problem, I will be happy to help you with it. I would still love to know about that weighing down a pedal overnight.

Big H
 

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Let me preface this by saying that this is not to be considered a sarcastic or smart elic remark but rather a curious question. I have read on this forum and others that weighing the pedal down helps. With brake bleeding experience for over 40 years on all types of vehicles, please explain to me how this method works. Trapped air bubbles just don't go away overnight, they may collect at one end of the line due to the pedal being weighed down, but the air can not escape the system unless a line or bleeder screw is loosened. I'm not saying it doesn't work because I will not go there. I'm only saying, I don't see how it works since the air is obviously still in the line. And, if your second depression of the pedal is not hard, then that's proof that the air is still there. The first depression will be slightly longer due to the initial fluid needed to move the pads against the rotors and the second will be less and firmer because of less fluid needed due to less travel of the pistons. Now I might add this little note. I once thought I still had air in my lines after bleeding them carefully and completely with certainty that all air was gone. Come to find out, if the front calipers are not positioned correctly over the rotors, you will get that "air in line sensation". This is because the pads are actually making the rotor bend slightly to one side. This can be observed by watching the rotor bend with someone squeezing the front brake lever. If any of you have that problem, I will be happy to help you with it. I would still love to know about that weighing down a pedal overnight.

Big H
It works, lay a 2' pipe over the brake pedal and hang 15-20 lbs on the end of it. Leave it for a couple days and report back. :=)

I assume it somehow pushes it to the reservoir, there is air already in there.
 

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Let me preface this by saying that this is not to be considered a sarcastic or smart elic remark but rather a curious question. I have read on this forum and others that weighing the pedal down helps. With brake bleeding experience for over 40 years on all types of vehicles, please explain to me how this method works. Trapped air bubbles just don't go away overnight, they may collect at one end of the line due to the pedal being weighed down, but the air can not escape the system unless a line or bleeder screw is loosened. I'm not saying it doesn't work because I will not go there. I'm only saying, I don't see how it works since the air is obviously still in the line. And, if your second depression of the pedal is not hard, then that's proof that the air is still there. The first depression will be slightly longer due to the initial fluid needed to move the pads against the rotors and the second will be less and firmer because of less fluid needed due to less travel of the pistons. Now I might add this little note. I once thought I still had air in my lines after bleeding them carefully and completely with certainty that all air was gone. Come to find out, if the front calipers are not positioned correctly over the rotors, you will get that "air in line sensation". This is because the pads are actually making the rotor bend slightly to one side. This can be observed by watching the rotor bend with someone squeezing the front brake lever. If any of you have that problem, I will be happy to help you with it. I would still love to know about that weighing down a pedal overnight.

Big H
My guess (and this is just a guess...). Putting pressure on the pedal puts pressure on the air, making the bubble(s) a lot smaller. It's a lot easier for a smaller bubble to travel upwards through the lines on its own (may take some time). Upwards usually ends at the master cylinder...
 

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It can work, but not always and it is only very temporary. I don't know why it works at all. I used to follow that procedure with my soft peddle, but since following the two extra steps in bleeding, the peddle has been super firm without the foollishment.

prs
 

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I have bleed many brakes and never had a problem with Honda's proceedure. The trick to get rid of any trapped air in the system is to power bleed. If you don't have a pressure bleeder then what also works is to apply max pressure to the peddal then crack the bleeder, if the fluid moves fast enough it will carry trapped air with it downhill to the caliper. No need to bleed from the fitting on the frame rail.
 

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I have bleed many brakes and never had a problem with Honda's proceedure. The trick to get rid of any trapped air in the system is to power bleed. If you don't have a pressure bleeder then what also works is to apply max pressure to the peddal then crack the bleeder, if the fluid moves fast enough it will carry trapped air with it downhill to the caliper. No need to bleed from the fitting on the frame rail.[/QUOTE

I don't have any problems either. I was just curious about all the forums that talk about weighting down the pedal with a brick or similar object to remove trapped air. Pressure bleeding goes way way back in the days of old when professional mechanic shops used them. Harbor Freight now offers a less expensive and smaller unit that uses pressure to bleed the system. Personally, I will stay away from it and stick with the old fashioned method since it has never let me down. But hey, that's just who I am. Thanks for all the feedback on this issue. I appreciate it.

Big H
 

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Let me know when they start teaching the "weight it down with a brick" method in the auto and moto tech schools... until then it's just another message board myth.
 

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Discussion Starter #14
I agree with Duckster. Putting pressure on the brake pedal overnight, or a couple of days does work. I did it on my 1200LTD and the pedal was rock hard ever since, right to the day I sold it. I have not tried it on the 1800.

As Taddpole suggested, I think the same thing, it pushes the air essentially back into the fluid in smaller bubbles that will now move in the system when bled. Thats why when I get ready to bleed them, I will put some weight on the pedal for a couple of days first, then bleed.

Cal-D: I have a mity vac and an electric vacuum pump that I used last time, and it didn't work. I put the electric vacume pump on the rear caliper and ran a whole bottle (smaller size) of fluid through it, non stop last time and the pedal was still mushy.....
 

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I agree with Duckster. Putting pressure on the brake pedal overnight, or a couple of days does work. I did it on my 1200LTD and the pedal was rock hard ever since, right to the day I sold it. I have not tried it on the 1800.

As Taddpole suggested, I think the same thing, it pushes the air essentially back into the fluid in smaller bubbles that will now move in the system when bled. Thats why when I get ready to bleed them, I will put some weight on the pedal for a couple of days first, then bleed.

Cal-D: I have a mity vac and an electric vacuum pump that I used last time, and it didn't work. I put the electric vacume pump on the rear caliper and ran a whole bottle (smaller size) of fluid through it, non stop last time and the pedal was still mushy.....
Without a pressure bleeder, use the mity vac to change the fluid but I would finish off with a few "pump and hold pressure-crack bleeder" method. For the rear brake have someone stand on the pedal with lots of pressure then crack the bleeder and quickly close, this will move the fluid fast enough to remove any trapped air. Repeat a few times till the pedal is solid.
 

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Let me know when they start teaching the "weight it down with a brick" method in the auto and moto tech schools... until then it's just another message board myth.
I never said GWG teaches it to the techs, I just said it works. Sorry I pi**ed you off.
 
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