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    #16
    Finally got the rear MC opened up and now I understand what Chuck was describing back on the first page. Vinegar did the trick but it is an acid so you can't leave it soaking in there forever. The MC looks good inside (no scoring or pitting) and I have a rebuild kit on the way so I'll likely install the new cup, piston, and spring. The circlip and rod going into the bottom of the MC are pretty freaking rusty. I threw the rod back in some vinegar so we'll see how it looks this evening.

    I'm still struggling to get the piston out of the front caliper. I tried soaking in Berryman's (this of course stripped the paint) with no luck. I tried soaking in vinegar and still no luck so I'll give it another day or two.

    In regard to MC sizes, I've been doing a lot of research on the topic. Thanks for bringing up the idea tkent. I called the guy who runs the Vintage Brakes site I posted earlier. I spent about 20 minutes on the phone with him, and he explained a lot of things to me. He believed a smaller MC would perform and feel better. I'll give it a try. Since this is my first bike, I don't know the difference between stock brakes and great brakes, so whatever I go with will be my new normal.

    With this info, I've been searching for a new smaller front MC. I'm trying to find something around 12mm or 1/2". I found this one on Ebay but it has small reservoir. As long as it holds enough to fill the piston chamber (and it wouldn't be much of a MC if it didn't), I should have nothing to worry about right? http://www.ebay.com/itm/7-8-RIGHT-AT...-/181774855203

    Also, thanks to Charles for mentioning Rennsport's stainless lines. Rennsport has been very helpful in figuring out what lengths and fittings to get and his prices are VERY good (half as much as Z1). Hoping to finalize plans this weekend so I can order the remaining parts. So close to getting this thing on the rode!
    Jordan

    1977 Suzuki GS750 (My first bike)
    2000 Kawasaki ZRX1100
    1973 BMW R75/5

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      #17
      If the pushrod for the rear master doesn't clean up, email me some pictures and dimensions. I may have the pieces from the rear master cylinder I'm replacing completely

      Comment


        #18
        Doesnt matter if the pushrod is a little pitted..it doesnt effect any functions of the master cylinder. If it bothers you a little flat black paint will disquise a lot of it. once its on the bike its mostly hidden by the frame anyway.
        MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
        1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

        NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


        I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

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          #19
          It's your neck. Fit a piece of crap cheap m/c if you like.
          ---- Dave

          Only a dog knows why a motorcyclist sticks his head out of a car window

          Comment


            #20
            Shrink tubing will cover the pitting as well
            MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
            1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

            NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


            I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

            Comment


              #21
              Good point about the rod. Appearance wasn't my concern but I am worried about the washer since it's locked on the rod. The washer is pretty rusty but I won't know if it's pitted til I get the rust off.Rear MC rod.jpg
              Jordan

              1977 Suzuki GS750 (My first bike)
              2000 Kawasaki ZRX1100
              1973 BMW R75/5

              Comment


                #22
                Its press fitted to the rod....it will never come off!!!!
                MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
                1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

                NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


                I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

                Comment


                  #23
                  Yep so I hope the washer is in good shape. or I have to get a new rod (thanks 850GT).

                  I guess the washer only serves as a mounting surface for the circlip. The cup inside holds the fluid. With a fresh circlip and new rubber boot, I should be OK.
                  Jordan

                  1977 Suzuki GS750 (My first bike)
                  2000 Kawasaki ZRX1100
                  1973 BMW R75/5

                  Comment


                    #24
                    It acts as a centering guide for the rod Guides it straight up and down when you step on the pedal. Yup on the clip and dust boot.
                    MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
                    1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

                    NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


                    I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

                    Comment


                      #25
                      Originally posted by Grimly View Post
                      It's your neck. Fit a piece of crap cheap m/c if you like.
                      I've been looking for a MC with 14mm bore or smaller and 10mm mirror mount that fits 7/8" bars. Any suggestions on new MC's below $100?

                      Outside of Ebay, I've found a 13mm non adjustable MC for $80 and a 14mm Kawasaki replica (that needs a hydraulic switch) for $50.
                      Jordan

                      1977 Suzuki GS750 (My first bike)
                      2000 Kawasaki ZRX1100
                      1973 BMW R75/5

                      Comment


                        #26
                        Originally posted by hannibal View Post
                        I've been looking for a MC with 14mm bore or smaller and 10mm mirror mount that fits 7/8" bars. Any suggestions on new MC's below $100?

                        Outside of Ebay, I've found a 13mm non adjustable MC for $80 and a 14mm Kawasaki replica (that needs a hydraulic switch) for $50.
                        What I do is get decent OEM m/c of the right size that were fitted to XJ900, Deauville (both 16mm / 5/8th, or for 14mm a Ninja EX500. Best to find a low-mileage example, but for peace of mind rebuild it with an OEM kit. Sure, it will cost more than an crappy Chinese EBay part but they're better and tougher and had decent quality control.
                        The Deauville m/cs for example, are Brembo, the others Nissin - and they don't make crap bits.
                        ---- Dave

                        Only a dog knows why a motorcyclist sticks his head out of a car window

                        Comment


                          #27
                          Thanks for the info Grimly. I do like the idea of finding and rebuilding an OEM MC. At least you know it's a quality part and will be practically brand new after a rebuild. The quality of the Ebay parts are unknown, and I see the same MC's priced anywhere from $15 to $75. It's hard to know their true value. Am I getting a great deal on a $75 MC or am I overpaying for a $15 MC? Who knows!

                          I am struggling to get the piston out of the front caliper. Soaking it in vinegar loosened it enough to spin the piston in the bore. But it takes a pliers and all my strength and weight just to get it to turn. At this rate, it'll be 6 months before I can twist it out. I tried compressed air, then Berrymans, then pumping it out with the MC, then the vinegar. No luck. I guess heat is the last resort, and I don't own a torch. I'm considering putting the whole caliper in the oven and see if that helps. Don't want to burn off the paint, cause that would be pretty stinky and smokey I'm guessing. I pulled off the metal ring around the bore so the only thing "holding" the piston in is the rubber O ring. I also saw a Youtube vid of a guy using a grease gun to push the caliper out. Has anyone tried this?

                          On the rear caliper, I managed to remove both pistons. It was quite tough at the time, but in hindsight, it was super easy compared to the front. But on the rear, I cannot get the metal rings off the caliper. I'm prepared to destroy the rings to get them off but I don't want to hurt the caliper body. I don't mind paying $5 each for new rings if I could just get them off.

                          Any advice on getting the front piston out or the rear rings off?
                          Jordan

                          1977 Suzuki GS750 (My first bike)
                          2000 Kawasaki ZRX1100
                          1973 BMW R75/5

                          Comment


                            #28
                            The front caliper piston should come out with compressed air, unless it's really lodged in there sideways due to over-application of brute force. I used a $10 bicycle pump to get mine out and it was full of crusted up brake fluid after having sat for well over a decade. A grease gun will work too but it's messier.

                            What metal rings are you talking about? Do you have a picture?
                            Charles
                            --
                            1979 Suzuki GS850G

                            Read BassCliff's GSR Greeting and Mega-Welcome!

                            Comment


                              #29
                              I incorrectly thought that the rears had a ring like the front. It does not.
                              Jordan

                              1977 Suzuki GS750 (My first bike)
                              2000 Kawasaki ZRX1100
                              1973 BMW R75/5

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