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Discussion Starter #1
Hey guys,
Not too long ago, I put on a new set of brake pads (EBC HH). They worked well at first, then the front brakes started getting soft. I noticed that one of the calipers was dragging, so I figured I just burned up the fluid. So, I rebuilt the calipers with new seals (they definitely needed it) and filled it/bled it with new fluid. Result: really soft front brakes. I bled it about 5 times, never any air coming out and without it helping. Just tried the compress-the-pistons technique, didn't help any either. Is there anything you guys can think of that would cause this? I can't figure out where any air would be hiding, and a master cylinder going bad doesn't usually cause the brakes to be soft.
Thanks for your help,
Neil
 

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Are you still using stock original brake lines? At almost 10 years old, they need to be replaced. A set of SS braided lines will do wonders for you.
 

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Are you still using stock original brake lines? At almost 10 years old, they need to be replaced. A set of SS braided lines will do wonders for you.
Word.


What about rotor thickness? I have no idea how long rotors last or even if thin rotors would cause the brakes to feel soft. Just thought I'd throw it out there.
 

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How are you bleeding your brakes?


It took me 1 hour to bleed my brakes. You want to keep bleeding right to left until you feel the hydraulic pressure build up (pump then release about 1000 times). I think you just need to bleed more.
 

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How are you bleeding your brakes?


It took me 1 hour to bleed my brakes. You want to keep bleeding right to left until you feel the hydraulic pressure build up (pump then release about 1000 times). I think you just need to bleed more.
bleeding a motorcycle actually takes that long? I have bleed a truck system and it was good to go after a few pumps.
 

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Discussion Starter #7
To bleed them, I do the traditional pump-pump-hold with the brake lever, then open and close the bleeder, I've probably ran a pint through since I last saw a bubble. I might have toasted one of the pads (getting a new set for the side anyway) but that shouldn't affect the firmness really, just how hard I have to pull to get it to stop. I usually do it on the side stand- I'm not sure whether that would change anything. Any other ideas on what to try before I have the shop mess with it?
-Neil
 

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Wrap a rag around the banjo. Put some pressure on the lever and crack the banjo. Retighten immediately when the lever bottoms out, never letting go of the lever. See if that helps.
 

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Try sanding the pads a little and cleaning the rotors with some brake clean on a clean rag. You may have some film on the pads and rotors that make them not grab as good as they should. Just my 2 cents.
 

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EBC pads have a tendency to warp their backing. Take the pads, put them on a sheet of glass with friction material facing up, and see if they lay flat. If not, there's your problem.

To make bleeding faster and easier, buy a vacuum bleeder. You can get one for about $20 from Harbor Freight.
 

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Discussion Starter #12
Hey, that was an interesting idea about the backing being warped, but I just checked them and, unfortunately they're flat as far as I can see. Is there anything that needs to be done to prime the master cylinder? I didn't see anything in the manual about it, but has anyone has trouble with air in there?
Thanks,
Neil
 

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Pull back on the brake lever hard and keep it down. Wait and see if after a minute it becomes easier to keep it down. If it does, you're having fluid escape past a seal, probably in the mc since you just rebuilt the calipers. If it's still fine after a couple minutes, then you're looking at air in your system somewhere. If you need to bleed it again, I strongly suggest picking up a vacuum bleeder. They're pretty cheap, do a great job, and make things much easier. Run a lot of fluid through the system, and make sure to tap on your brake lines to dislodge any air bubbles.
 

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Hey, that was an interesting idea about the backing being warped, but I just checked them and, unfortunately they're flat as far as I can see. Is there anything that needs to be done to prime the master cylinder? I didn't see anything in the manual about it, but has anyone has trouble with air in there?
Thanks,
Neil

Do what andyauger said. I had to do this a few weeks ago with a new brake system. Fixed it immediately.
 

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bleeding a motorcycle actually takes that long? I have bleed a truck system and it was good to go after a few pumps.
I have completely bleed car brake systems after installing a new MC and it didn't take half as long as the bike. When I did it I was intalling a new set of GSX-R radial brake calipers with the SV OEM brake MC. I'm sure having someone help whould be nice, but I'm not sure why it took soo long to build up hydraulic pressure in the system (maybe I should go with the bigger MC). I have used the vacuum system to bleed brakes in the past and it's worth the extra $$.
 

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Discussion Starter #16
Hey, regarding the method andyauger mentioned, which banjo bolt are you referring to - the union bolts at the calipers, at the splitter, or what?
-Neil
 

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I think Andy and JBS have it right. Cracking the banjo has worked for me on stubborn brake bleeds. I've had the exact same problem.

Front brake line is nearly vertical so what I think happens is the air bubble rises in the line faster than you can pump it out.
 
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