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Community Manager
Sudhanshu
Community Manager
November 11, 2025
Solved

Front Brake Master Cylinder – fitment & spongy lever after upgrade

  • November 11, 2025
  • 40 replies
  • 260 views

Replacing stock master cylinder with an aftermarket unit. Lever feels a bit spongy even after a quick bleed. Looking for best-practice on piston size, banjo/crush washers, ABS compatibility, and bleed order.

    Best answer by Sudhanshu

    Full bleed order matters on ABS bikes: MC → ABS module → calipers. Vacuum + reverse bleed helps.

    40 replies

    S
    Community Manager
    SudhanshuAuthorAnswer
    Community Manager
    November 11, 2025

    Full bleed order matters on ABS bikes: MC → ABS module → calipers. Vacuum + reverse bleed helps.

      S
      Community Manager
      SudhanshuAuthor
      Community Manager
      November 11, 2025

      If lever firms up then fades, air is trapped in the ABS modulator—cycle it.

        S
        Community Manager
        SudhanshuAuthor
        Community Manager
        November 11, 2025

        Check the tiny return port in the reservoir isn’t clogged.

          S
          Community Manager
          SudhanshuAuthor
          Community Manager
          November 11, 2025

          Quick data point: swapping in fresh crush washers and re-torquing the banjo stopped the slow lever creep for me.

          sudhanshu_sabharwal
          sudhanshu_sabharwal
          Sudhanshu Sabharwal
          December 10, 2025

          Testing L2 single page 

          Gainsight Product manager
            sudhanshu_sabharwal
            sudhanshu_sabharwal
            Sudhanshu Sabharwal
            November 20, 2025

            Reverse-bleed from caliper with a syringe to push air up

            Gainsight Product manager
            sudhanshu_sabharwal
            sudhanshu_sabharwal
            Sudhanshu Sabharwal
            December 11, 2025

            your final bleed order/torques; it helps the next service.

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              sudhanshu_sabharwal
              sudhanshu_sabharwal
              Sudhanshu Sabharwal
              November 20, 2025

              Test level 1

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                Sudhanshu Sabharwal
                December 11, 2025

                trial

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                  Sudhanshu Sabharwal
                  November 20, 2025

                  Test L1

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                  Sudhanshu Sabharwal
                  December 11, 2025

                  Check

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                    Sudhanshu Sabharwal
                    December 11, 2025

                    3rd level

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                      November 20, 2025

                      Test L1 again

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                      December 10, 2025

                      Test L1 pagination control

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                      January 9, 2026

                      L2

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                        Sudhanshu Sabharwal
                        January 9, 2026

                        @sudhanshu_sabharwal L3

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                          December 10, 2025

                          Test L1 pagination control

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                          December 10, 2025

                          Test L1 pagination in control

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                          December 10, 2025

                          Test L1 pagination in control

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