About The Product
- Designed to perfectly compliment KMC`s line of chains
- Carefully designed lifting and lowering shifting ramps ensure improved shifting, efficiency and stability
- Optimised gearing results in fewer large jumps in tooth count for smooth, predictable progressive shifting
- Shimano HG compatible interface
Upgrade Your Ride with the KMC REACT 10-Speed Cassette - Precision, Durability, and Seamless Shifting
Optimized for performance and engineered for durability, the KMC REACT Cassette (11-42t, HG driver compatible, Black) is the perfect upgrade for mountain biking, gravel riding, and adventure cyclists seeking reliable gear shifting across challenging terrains. Crafted from high-strength steel and meticulously designed with advanced component technology, this 10-speed cassette delivers smooth, precise shifting and enhanced drivetrain lifespan.
Materials & Engineering Excellence
Constructed from premium high-strength steel, the KMC REACT cassette ensures long-lasting durability and resistance to wear under demanding riding conditions. Its robust construction is paired with advanced ascent and descent ramps, engineered to guide the chain flawlessly for improved shifting accuracy and efficiency.
Components & Technology
Featuring a range of cogs from 11 to 42 teeth-optimized for diverse terrain-this cassette boasts an innovative design that includes lifted and lowered ramps. These elements facilitate smooth chain engagement; the lifting ramps elevate the chain seamlessly onto larger cogs, while the lowering ramps quickly align the chain for precise shifting. Compatible with Shimano HG freehub bodies (8-11 speed), it provides universal compatibility and easy installation.
Style & Use Case
The sleek black finish adds a modern, streamlined look to any mountain bike or gravel bike setup. Whether you're conquering steep ascents, technical descents, or multi-day gravel adventures, the REACT cassette is engineered to enhance your riding experience. Its versatile gear range allows for effortless cadence management, making it ideal for aggressive trail riding, endurance cycling, or recreational exploring.
Innovative Features & Differentiators
- Precision shifting with optimized cog sizes (11-13-15-18-21-24-28-32-36-42) promotes smoother gear transitions and accurate chain retention.
- High-strength steel construction extends component lifespan, even under high torque and dirt exposure.
- Designed specifically to match KMC chains like e10, X10, X10 EL, and X10 SL, ensuring excellent compatibility and minimal friction.
- Lightweight at only 593 grams, it offers an excellent balance of strength and weight savings for competitive or trail riding.
Key Specifications:
- Gear Range: 11-42T
- Cogs: 11, 13, 15, 18, 21, 24, 28, 32, 36, 42 teeth
- Drivetrain Speed: 10-Speed
- Compatibility: Shimano HG freehub bodies (8-11 speed)
- Material: High-strength steel
- Color: Black
- Model: GMX10-3
- Weight: 593g
Elevate your mountain biking or gravel adventures with the KMC REACT Cassette-designed for smooth shifts, exceptional durability, and versatile performance across all riding conditions. Upgrade now for a more efficient, reliable drivetrain that keeps you pushing further and riding smarter.
- Optimized for 10-speed drivetrains, the KMC REACT Cassette features a refined 11-42t gear range, ideal for versatile off-road and mountain biking applications.
- Constructed from high-strength steel with precise machining, this cassette delivers durable performance and long-lasting reliability even under demanding riding conditions.
- Innovative ascent and descent ramps improve shifting performance by ensuring smooth, accurate gear changes, reducing chain slippage across diverse terrains.
- Designed to seamlessly integrate with Shimano HG freehub bodies, the REACT cassette offers exceptional compatibility with a wide range of wheelsets, enhancing overall drivetrain efficiency.
- Stylish black finish combined with advanced gear engineering makes the KMC REACT cassette perfect for riders seeking reliable, high-performance components with a sleek, professional look.
| Specification | Value |
|---|---|
| Manufacturer | KMC |
| Manufacturer Part No. | CSTE00523 |
| Universal Product Code | 766759000523 |
| Invoice Description | FH CASS KMC GMX10-3 11-42 BK 10s |
| Shipping Weight | 1.70 lbs. |
| Package Dimensions | 9.6 x 9.1 x 1.7 |
| Country of Origin | TAIWAN |
| Range | 11-42t |
| Gears | 10sp |
| Cogs | 11,13,15,18,21,24,28,32,36,42 |
| Color | Black |
| Model | GMX10-3 |
- 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
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Storefront name: Bike Junkies
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Address: 940 Calle Amanecer, Suite N
San Clemente, CA 92673 -
Phone: 800-605-2152
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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
