My motorcycle brake lever has no pressure

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I tried bleeding the brakes on my ’07 Honda Rebel, thinking it would be a straightforward DIY job. But now, I’m left with a brake lever that’s completely limp, offering no resistance whatsoever. I’ve been at this for hours, following every guide I could find, but it’s like there’s an endless supply of air in the lines. I’m new to motorcycle maintenance and really want to get this right. Can anyone shed some light on what I might be doing wrong?

Response

I’ve been in your shoes, and I know how frustrating this can be. When I faced a similar issue, using a vacuum pump for bleeding turned things around for me. It might take a bit of time and patience, but it’s worth a shot. Don’t lose hope just yet!

Solutions that Worked for Users

SolutionUsers Who Found SuccessApprox. Cost (USD)Time Needed (Minutes)
Vacuum Bleeding5$20 – $5030 – 60
Reverse Bleeding4$10 – $3045 – 90
Bleeding at Master Cylinder3Free – $10 (for tools)20 – 40
Tapping Calipers While Bleeding2Free30 – 60
Bench Bleeding Master Cylinder1Free – $10 (for tools)60 – 120

Solutions

Vacuum Bleeding

  • What I Did: Employed a vacuum pump to methodically extract fluid and air from the brake system.
  • Outcome: Successfully expelled all air, restoring the much-needed pressure to the brake lever.
  • Personal Experience: Required patience, but the results were worth the effort.
  • Estimated Cost: $20 – $50
  • Time Needed: 30 – 60 minutes
  • Detailed Steps:
    1. Setup: Attach the vacuum pump to the brake bleeder valve securely.
    2. Pumping: Start pumping to create a consistent vacuum, drawing out fluid and air.
    3. Fluid Level Monitoring: Keep a close eye on the master cylinder’s fluid level to avoid introducing new air.
    4. Repeat Process: Continue this process, moving from one brake to the other if necessary, until no more air bubbles are visible.
    5. Final Check: After completing the process, test the brake lever for firmness.
  • Handy Tips:
    • Ensure a tight seal around the bleeder valve to prevent external air intake.
    • Consider doing this in a well-ventilated area as brake fluid fumes can be harmful.
    • Wear gloves to protect your hands from brake fluid.

Reverse Bleeding

  • What I Did: Pushed brake fluid upwards through the system to displace and expel air bubbles.
  • Outcome: Air bubbles effectively moved upwards and expelled, restoring brake lever pressure.
  • Personal Experience: Found this method particularly effective for stubborn air locks.
  • Estimated Cost: $10 – $30
  • Time Needed: 45 – 90 minutes
  • Detailed Steps:
    1. Preparation: Fill a clean syringe with fresh brake fluid.
    2. Connection: Attach the syringe to the bleeder valve at the lowest point of the brake system.
    3. Fluid Injection: Gently push the fluid into the system, observing the master cylinder for overflow.
    4. Air Displacement: Continue this process until air bubbles cease to appear at the master cylinder.
    5. System Check: After completing, test the brake lever for improved pressure.
  • Handy Tips:
    • Use a clear tube between the syringe and the bleeder valve to visibly monitor air bubbles.
    • Ensure the master cylinder does not overflow; use a rag to catch any spills.
    • If resistance is felt while injecting fluid, pause to avoid damaging the system.

Bleeding at Master Cylinder

  • What I Did: Started the bleeding process directly at the master cylinder to tackle air trapped at high points.
  • Outcome: Successfully removed trapped air, significantly improving lever pressure.
  • Personal Experience: A bit messy but highly effective.
  • Estimated Cost: Free – $10 (for tools)
  • Time Needed: 20 – 40 minutes
  • Detailed Steps:
    1. Positioning: Elevate the motorcycle or adjust the handlebars so the master cylinder is the highest point.
    2. Bleeding Process: Open the master cylinder bleeder valve and pump the brake lever.
    3. Valve Management: Close the valve before releasing the lever to prevent air re-entry.
    4. Repetition: Repeat this process until air bubbles no longer appear.
    5. System Evaluation: Test the brake lever for firmness and responsiveness.
  • Handy Tips:
    • Use a piece of clear tubing on the bleeder valve to see air bubbles exiting the system.
    • Keep a rag handy to clean up any spills immediately, as brake fluid can damage paint.
    • If the lever still feels spongy, consider repeating the process or checking for leaks.

Tapping Calipers While Bleeding

  • What I Did: Applied gentle taps to the brake calipers during the bleeding process to dislodge trapped air.
  • Outcome: Helped in dislodging stubborn air bubbles, allowing them to escape and restoring pressure.
  • Personal Experience: Simple yet effective, especially for calipers with complex internal passages.
  • Estimated Cost: Free
  • Time Needed: 30 – 60 minutes
  • Detailed Steps:
    1. Initial Bleeding: Start with the standard bleeding process to remove as much air as possible.
    2. Caliper Tapping: While someone else operates the brake lever, gently tap the caliper with a soft mallet or back of a screwdriver.
    3. Observation: Watch for air bubbles exiting the system and continue until they cease.
    4. Final Checks: Test the brake lever for improved firmness.
  • Handy Tips:
    • Tapping should be gentle to avoid damaging the caliper.
    • If one caliper is particularly problematic, focus more time on it.
    • After completing, check for any leaks around the caliper.

Bench Bleeding Master Cylinder

  • What I Did: Removed and bled the master cylinder separately on a bench to ensure thorough air removal.
  • Outcome: Ensured complete air removal from the master cylinder, a critical step in restoring system pressure.
  • Personal Experience: Required re-bleeding the entire system afterward but was effective.
  • Estimated Cost: Free – $10 (for tools)
  • Time Needed: 60 – 120 minutes
  • Detailed Steps:
    1. Removal: Carefully remove the master cylinder from the motorcycle.
    2. Secure Setup: Place the master cylinder in a vise or secure it on a bench.
    3. Thorough Bleeding: Bleed the master cylinder, ensuring all air is expelled.
    4. Reinstallation: Reattach the master cylinder to the bike.
    5. System Re-bleeding: Bleed the entire brake system again to ensure no air remains.
  • Handy Tips:
    • Cover your workbench with rags or a protective sheet to catch any spills.
    • Be meticulous in reattaching the master cylinder to avoid introducing new air.
    • After reinstallation, double-check all connections for tightness and leaks.

Motorcycle Models Where This Worked:

  • Various models, including 2007 Honda Rebel, Yamaha SRX600, and others.

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