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i keep bleeding the front and rear brakes but no real pressure.

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    i keep bleeding the front and rear brakes but no real pressure.

    So i rebuilt the front and rear brake calipers with all new rubbers and followed the instructions on basscliffs website. They are on the bike now and when i tried bleeding them putting new fluids through it the brakes get some pressure to them but nothing significant. I kept bleeding the front brake today and it didn't get to anything it was before. its even more squishy now and i have to pump it a few times before it even stops. it has new brake pads in it too. is their some sort of procedure im missing in filling these brakes. I open the lid squeeze a few times hold it down , then open the bleeder nipple, close it the release and pump more?

    #2
    You could try to lock your brakes overnight and see if it will gravity bleed. I had the same trouble and tying my lever down and wedging something in between the pedal and frame overnight helped firm them up quite a bit. I gave the lines a good wiggle and the frame a good thumping too in order to loosen any air bubbles in the lines.

    It's a good idea to do that anyway to help identify any potential leaks IMO. If fluid can get out, air can get in.

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      #3
      whenever i bleed any brakes, here is a trick i have used that has helped me out more than once. i put a clear piece of tubing on the nipple of the bleeder so that it runs uphill before it runs down into the bottle or whatever i am pumping the fluid into. that way i can see the bubbles coming out. sometimes, long after all the big bubbles are gone, i get lots of little bubbles that i would not know were there if i didn't have the visual. also, just because the caliper is on the bike doesn't mean that the bleeder is at the highest point. try taking it off and blocking the pads and see if you get any more big bubbles...

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        #4
        Do you pump the master, hold the lever, unlock the bleed nipple, re-lock the nipple, then pump again? That's the proper method. Use a clear hose on the nipple so you can see the bubbles, as airbornespud recommends

        Assuming you were already doing the above, it sounds like your master cylinders don't have fluid in the pistons and are not pumping. It helps to "pre-bleed" the master cylinder, as the fluid in the piston also seals the piston for pumping. The easiest way would be to use a Mighty Vac or similar pump to pull fluid through the master cylinder and down into the calipers.

        You might also want to take a look at this tip I posted to get the last bit of trapped air back out the top of the system through the master cylinder.
        Last edited by Guest; 05-23-2012, 01:23 PM.

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          #5
          This didn't have anything to do with the problem you have now, though how old are you brake lines? Maybe time to replace them as well during this time.
          sigpicMrBill Been a GSR member on and off since April 2002
          1980 GS 750E Bought new in Feb of 1980
          2015 CAN AM RTS


          Stuff I've done to my bike:dancing: 1100E front end with new Sonic springs, 1100E swing arm conversion with new Progressive shocks installed, 530 sprockets/chain conversion, new SS brake lines, new brake pads. New SS fasteners through out. Rebuilt carbs, new EBC clutch springs and horn installed. New paint. Motor runs strong.

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            #6
            ill try a few of the tips you guys have told me and the brake lines look like stock.. however i have no money at the moment to replace them i was hoping they would last for a little bit longer

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              #7
              any luck yet?

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                #8
                Stock lines can really make your lever feel like mush. The old rubber lines were recommended by Suzuki to be replaced every two years. I've rarely seen a Gs that didn't have stainless replacement lines already have lines that were anywhere near only two years old. The old rubber lines will get weak and when you pull the lever, they'll expand/swell vs forcing the fluid to the caliper.

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                  #9
                  Mighty Vac...problems solved

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                    #10
                    Aftermarket K&L caliper seal kits can cause problems like this because they fit too tight and don't let the caliper piston move close enough to the disc. Tieing back the lever sometimes helps, because given enough time and pressure in the system the caliper piston will slowly migrate closer to the disc where they belong.
                    Ed

                    To measure is to know.

                    Mikuni O-ring Kits For Sale...https://www.thegsresources.com/_foru...ts#post1703182

                    Top Newbie Mistakes thread...http://www.thegsresources.com/_forum...d.php?t=171846

                    Carb rebuild tutorial...https://gsarchive.bwringer.com/mtsac...d_Tutorial.pdf

                    KZ750E Rebuild Thread...http://www.thegsresources.com/_forum...0-Resurrection

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                      #11
                      As the other guy said, You probably need to prime the master cylinder.
                      Just plug your thumb over the MC hole, squeeze the lever a buncha times to build pressure, then let your thumb off just a Hair, and let the air hiss out.
                      Repeat this a few times until solid fluid comes out, then quickly re-attach the upper brake
                      line.

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