Worn master cylinder seals cause a soft, spongy brake pedal, fluid leaks and inconsistent braking. This BrakeCrafters rear brake master cylinder rebuild kit restores firm, consistent hydraulic pressure on your Honda CRF450R, CRF250R, CRF450X, CRF250X, CRF250L, CR125R, CR250R (select 1981-2021 models) with high-quality, durable replacement components. It includes a new master cylinder piston along with fresh seals and hardware for a complete rebuild of your rear brake master cylinder. Red rubber grease is included for assembly. Bleed the system with fresh fluid after the rebuild for best results.
- Rebuilds the rear brake master cylinder
- High-quality, durable replacement seals for a precise fit
- Restores a firm, consistent brake pedal
- Stops fluid leaks and restores consistent hydraulic pressure
- Includes a new master cylinder piston
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Kit includes: 1 x Master Cylinder Piston, 1 x Return Spring, 1 x Primary Seal, 1 x Secondary Seal, 1 x Gaiter Boot, 1 x Circlip, 2 x Copper Crush Washers, 1 x Pot of Red Rubber Grease
- Red rubber grease included for assembly: lubricates components, protects against dry burn and prevents rubber seals from swelling or hardening
- Fitment-specific: confirm your year and model in the fitment table before ordering
- Bleed the system with fresh fluid after installation
- Hydraulic components should be installed by a qualified mechanic
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Brand: BrakeCrafters
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Part Number: BC138M-R
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Product Type: Master cylinder rebuild kit
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Position: Rear
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Kit Contents: 1 x Master Cylinder Piston, 1 x Return Spring, 1 x Primary Seal, 1 x Secondary Seal, 1 x Gaiter Boot, 1 x Circlip, 2 x Copper Crush Washers, 1 x Pot of Red Rubber Grease
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Fitment: Honda CR125R (1981-2007), CR250R (1981-2007), CRF250L (2013-2015), CRF250R (2004-2012, 2020), CRF250X (2004-2017), CRF450R (2002-2021), CRF450X (2005-2018)
New piston included*High-quality, durable seals*Restores firm brake pedal*Stops fluid leaks*Red rubber grease included
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All orders are sent via USPS Ground Advantage or UPS Ground Saver as standard unless otherwise stated. We also offer for US customers optional USPS Priority Shipping and FedEx Expedited Shipping. Please select this at checkout if you wish to elect this shipping method.
All international customers must submit a telephone number at checkout. Please note our goods ship exclusive of duties. You may be subject to a duties and customs fees at destination. Any applicable duty and customs charges are the responsibility of the customer.
We accept returns within 14 days of receipt of your item. In all cases, with the exception of defect or fulfillment error, shipping costs are the responsibility of the customer and non-refundable.
Return authorization is required in order to process your return. If you wish to return any item purchased from brakecrafters.com please contact us at sales@brakecrafters.com quoting your order number in the subject line of the email. Unless otherwise stated return shipping is the responsibility of the customer.
We may from time to time offer final sale markdowns. We cannot accept returns on these items. Where these terms are in effect they will be clearly indicated on our online store.
For more information, please visit our SHIPPING, FULFILLMENT AND RETURNS page.
At Brakecrafters, we strive to provide the most accurate fitment information in the industry. However, because much of our catalog covers vintage machinery—often relying on data that is 30 to 60 years old—it is impossible to guarantee 100% accuracy in every instance.
Please review the following terms regarding your purchase:
Our Commitment to Accuracy
- Data Integrity: We continuously update our database to ensure our listings reflect the best available information.
- Continuous Improvement: When a fitment error is identified, we don't just fix the order; we update our master records immediately to prevent the error from recurring for others.
- The "Make It Right" Guarantee: If you receive a part that does not fit your specific year, make, or model despite our listing, we are committed to resolving the issue and ensuring you get what you need for a successful repair.
How You Can Help
In the rare event of a discrepancy, we may ask for your assistance. This might include providing:
- Photos of the original part alongside the new part.
- Casting numbers or specific measurements from your master cylinder or calipers. Use Millimeters for better Accuracy.
- VIN or Production Date information is not actually helpful to us; we are not a brand dealer.
Your feedback is a vital part of maintaining the integrity of the vintage motorcycle community's technical data. By working together, we can keep these classic machines on the road safely.
Note: Always verify your specific components before beginning installation. If something looks different than the OEM part you removed, please contact us before proceeding with the rebuild.
