About The Product
- A variety of tools for reaming, tapping and facing bicycle headtubes and bottom brackets
Upgrade your bicycle maintenance toolkit with the Park Tool 789 Head Tube Reamer Replacement Bit - 55.95mm for ZS56 and EC56 Headsets. Designed with precision engineering and durable materials, this essential component ensures smooth, accurate head tube reaming for optimal headset fit and performance.
Materials & Construction
Made from high-quality, hardened steel, the Park Tool 789 replacement bit offers exceptional durability and resistance to wear, ensuring long-lasting precision during repeated use. Its robust build guarantees consistent results, even under rigorous workshop conditions.
Performance & Engineering
Engineered for perfect compatibility with Park Tool's 690-XXL Facing Cutter and 750 Centering Cone Adapter, this reamer reams head tube inner diameters to exactly 55.95mm. It enables precise preparation of head tubes to accept "internal" headset cups with 55.99 - 56.04mm O.D., adhering to the 1-1/2 ZS (Zero Stack) standard. This ensures a snug, secure fit for ZS56 and EC56 headsets, optimizing steering performance and ride quality.
Components & Technology
The reamer features specialized cutting geometry designed for clean, burr-free reaming, reducing installation time and enhancing headset longevity. Its compatibility with standard head tube diameters makes it a versatile choice for bike shops and DIY enthusiasts alike.
Style & Use Case
Perfect for professional bicycle shops and serious home mechanics, the Park Tool 789 Head Tube Reamer Replacement Bit is ideal for bike frame builders, rebuilders, and refurbishers who demand precise, reliable head tube preparation. Its straightforward design makes it easy to install and use with compatible facing and reaming tools, streamlining cycle assembly and maintenance.
Innovative & Differentiating Features
This genuine Park Tool replacement bit ensures factory-quality standards and seamless integration with existing equipment. Its size-specific design addresses common head tube reaming needs for 1-1/2 ZS headsets, elevating your workshop's capability to deliver precise, high-performance bicycle builds and repairs.
Specifications:
- Size: 55.92mm
- Tool Type: Reamer
- Compatibility: 1-1/2" ZS Headset (ZS56, EC56)
- Model: 789
Enhance your bike maintenance arsenal with the reliable, high-precision Park Tool 789 Head Tube Reamer Replacement Bit - the professional choice for accurate head tube reaming and superior cycling performance.
- Precise Compatibility: Designed specifically for ZS56 and EC56 headsets, this 55.95mm Head Tube Reamer Bit ensures accurate, clean machining of head tubes for a perfect headset fit.
- Premium Material Construction: Manufactured from high-strength, durable steel to withstand professional use, providing long-lasting performance and reliable reaming every time.
- Optimized for Performance & Engineering: Compatible with Park Tool's 690-XXL Facing Cutter and 750 Centering Cone Adapter, enabling seamless integration into your bike maintenance setup for precise head tube finishing.
- Versatile Use Case: Ideal for bicycle shops and professional mechanics performing head tube reaming on 1-1/2" ZS standard headsets, ensuring optimal headset installation and cycling performance.
- Innovative Design Features: Engineered to ream head tube I.D. to exactly 55.95mm, facilitating accurate internal diameter sizing and helping maintain the highest standards of bike build quality.
| Specification | Value |
|---|---|
| Manufacturer | PARK TOOL |
| Manufacturer Part No. | 789 |
| Universal Product Code | 763477013927 |
| Invoice Description | TOOL HEAD TUBE REAMER PARK 789 REAMER 55.92mm |
| Shipping Weight | 0.59 lbs. |
| Package Dimensions | 2.55 x 3.05 x 1.15 |
| Country of Origin | UNITED STATES |
| Tool Type | Reamer |
| Compatibility | for 1-1/2" ZS Headset |
| Size | 55.92mm |
| Model | 789 |
- Supplier:
- JBI
Bike Junkies offers no‑hassle returns and exchanges within 60 days of delivery. We want every customer to feel confident when shopping with us, and our return process is designed to be simple, fair, and fast.
Return Eligibility
To qualify for a return or exchange, the following conditions must be met:
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The item must be in new, unused, and uninstalled condition.
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All original packaging, tags, hardware, and accessories must be included and intact.
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Items showing wear, installation marks, damage, or improper use cannot be accepted.
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An order number is required.
Once your return is received at our warehouse, a refund will be issued within 5 days after inspection.
Refunds
Refunds are issued to the original form of payment once the returned item has been received and approved. If we are unable to refund to the original payment method, the refund will be issued as store credit.
Depending on your bank or credit card provider, it may take an additional 2–3 business days for the refund to appear in your account.
Exchanges
To make an exchange, simply complete the return process and then place a new order for the item you want instead. This ensures the replacement item is reserved and ships quickly.
How to Start a Return
To request a Return Authorization (RA#), contact us at support@bikejunkies.com. Please include your order number and the item you wish to return.
Once approved:
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You will receive a Return Authorization email with instructions.
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Print the prepaid label provided by us. ($9.99 will be deducted from your refund)
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Ship the item back within 7 days of the RA being issued as RA #'s are only valid for 7 days.
Please do not tape anything to the original product packaging. Place the item inside a proper shipping box. Using the manufacturer’s box as the shipping container will result in damage and the return may be rejected.
Be sure to keep your return tracking number. Powersport Junkies is not responsible for lost return shipments. You will receive a confirmation email once your return has been processed and refunded.
Defective, Incorrect, or Damaged Items
If you receive a defective, damaged, or incorrectly shipped item, contact us immediately. We will cover the return shipping cost and ensure the issue is resolved quickly.
Non‑Returnable Items
Certain items cannot be returned, including:
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Electronics with opened packaging or broken manufacturer seals
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Any part that has been installed or shows installation attempts
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Tools or chemicals that have been opened or unsealed
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Open‑box items with destroyed or missing packaging
Our Info
-
Storefront name: Bike Junkies
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Address: 940 Calle Amanecer, Suite N
San Clemente, CA 92673 -
Phone: 800-605-2152
-
Support email: support@bikejunkies.com
- Support hours + timezone:
Monday-Friday: 9:00 AM-5:00 PM PST
Saturday: 9:00 AM-3:00 PM PST
Sunday: Closed
This Shipping Policy explains how orders are processed, handled, and delivered by Bike Junkies, including delivery timelines, shipping coverage, and special conditions for military addresses. It is designed to give customers a clear understanding of what to expect when placing an order.
Bike Junkies is proud to be an authorized dealer of the brands we currently offer. When you purchase from us, you are guaranteed to receive genuine, brand-new products backed by the full manufacturer warranty. We work directly with the manufacturers to ensure you receive the highest quality service and support.
Order Processing and Handling
Orders are processed quickly to ensure fast delivery. Our standard handling time is 0–1 business days. Order cutoff time is 12 PM PST Monday-Friday and orders placed after that will be shipped shipped next business day.
Transit Times
Once shipped, orders typically arrive within 2–3 business days. Transit times may vary slightly depending on the destination, weather conditions, or carrier-related delays. Delivery estimates apply only after the order has left our facility.
Delivery Schedule
Standard delivery occurs Monday through Friday. Saturday delivery may be available.
Shipping Coverage
Bike Junkies offers free shipping to the lower 48 states of the United States. We do not ship to the following locations:
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Alaska
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Hawaii
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Puerto Rico
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Any international destination outside the United States
Orders placed with shipping addresses in restricted locations will be canceled and refunded.
Military Shipping (APO/FPO)
Bike Junkies ships to APO/FPO military addresses using USPS only.
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We cannot ship hazardous materials or oversized items to military addresses due to carrier and military mail restrictions.
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Transit times to APO/FPO locations may vary significantly depending on military mail processing.
Address Accuracy and Delivery Issues
Customers are responsible for ensuring that all shipping information provided at checkout is accurate and complete. Bike Junkies is not responsible for delays, lost packages, or delivery failures caused by incorrect or incomplete addresses. If a package is returned due to an address error, additional shipping charges may apply to resend the order.
Lost, Delayed, or Damaged Shipments
If a shipment is delayed, lost, or arrives damaged, customers should contact us promptly so we can assist with initiating a claim or resolving the issue with the carrier. While we support the process, final decisions regarding claims are made by the carrier.
Tracking Information
A tracking number is provided via email once the shipping label has been created. Tracking updates may take up to 24 hours to appear after the label is generated.
Shipping Restrictions
Certain items may be subject to shipping restrictions due to size, weight, or hazardous material regulations. If an order cannot be shipped due to such restrictions, we will notify the customer to arrange an alternative solution.
Our Info
-
Storefront name: Bike Junkies
-
Address: 940 Calle Amanecer, Suite N
San Clemente, CA 92673 -
Phone: 800-605-2152
-
Support email: support@bikejunkies.com
- Support hours + timezone:
Monday-Friday: 9:00 AM-5:00 PM PST
Saturday: 9:00 AM-3:00 PM PST
Sunday: Closed
For warranty issues please contact us at support@bikejunkies.com. Each Brand is different and we can provide instruction to complete warranty issues.
Bike Junkies is proud to be an authorized dealer of the brands we currently offer. When you purchase from us, you are guaranteed to receive genuine, brand-new products backed by the full manufacturer warranty. We work directly with the manufacturers to ensure you receive the highest quality service and support.
Our Info
-
Storefront name: Bike Junkies
-
Address: 940 Calle Amanecer, Suite N
San Clemente, CA 92673 -
Phone: 800-605-2152
-
Support email: support@bikejunkies.com
- Support hours + timezone:
Monday-Friday: 9:00 AM-5:00 PM PST
Saturday: 9:00 AM-3:00 PM PST
Sunday: Closed
