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SKU: CY6760

Shimano SM-JC40 Di2 External Frame Junction Box - 4-Port E-Tube Wiring System for Electronic Shifting, Durable Aluminum Mount, Compatible with Shimano Di2 Electronic Groupsets, Optimized for Precise Shifting and Seamless Bike Integration

Regular price $41.83
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This is a pre order item. We will ship it when it comes in stock.

$10 Gift Card

at 250 points

$25 Gift Card

at 500 points

$75 Gift Card

at 1,000 points

Description

Enhance your Shimano Di2 electronic shifting setup with the Shimano SM-JC40 Di2 External Frame Junction Box - the ultimate 4-port junction for seamless electronic gear control. Crafted from high-quality materials and engineered for precision, this junction box ensures reliable connectivity and optimal performance across your drivetrain system.

Materials & Construction:

Manufactured with durable, lightweight materials designed to withstand harsh cycling conditions, the SM-JC40 provides long-lasting performance and impeccable build quality. Its robust housing protects electronic components from moisture, dirt, and vibrations, making it ideal for all riding environments.

Performance & Engineering:

Designed for optimal electronic communication, this junction box mounts securely underneath the bottom bracket shell, offering a clean aesthetic and streamlined setup. It efficiently connects via SD50 E-tube wires to four critical points: front derailleur, rear derailleur, cockpit junction box, and battery mount. This setup enables quick, precise shifting with minimal cable clutter, enhancing your bike's overall responsiveness.

Components & Technology:

The SM-JC40 is compatible exclusively with Shimano Di2 electronic shifting systems, ensuring a seamless digital interface. It supports firmware updates through the Di2 system checker, compatible with Shimano's E-tube technology, facilitating future-proof connectivity and improved system stability. Its design supports all Di2 components operating under the same firmware version-preventing malfunctions and ensuring consistent gear shifts.

Style & Use Case:

Perfect for road, mountain, and gravel bikes, the Shimano SM-JC40 junction box offers a clean and professional installation. Its external mounting makes maintenance straightforward while preserving the sleek aesthetics of modern bicycles. Ideal for bike builders and DIY enthusiasts seeking a reliable, high-performance junction solution.

Innovative & Differentiating Features:

- External mounting design for easy installation and troubleshooting

- Supports four connection ports for versatile system integration

- Designed for high compatibility with Shimano's latest Di2 firmware versions

- Facilitates firmware updates to maintain system performance

- Compatible with E-tube wiring for flexible routing options

Upgrade your Shimano Di2 electronic drivetrain with the Shimano SM-JC40 Di2 External Frame Junction Box - a key component that delivers precision, reliability, and sleek integration for advanced cyclists and bike builders alike.

  • Precisely engineered Shimano SM-JC40 Di2 External Frame Junction Box with 4-port connectivity for seamless electronic shifting integration.
  • Constructed from high-quality, durable materials designed to withstand demanding cycling conditions and ensure long-lasting performance.
  • Features advanced SD50 E-tube wiring compatibility, allowing reliable connection between front derailleur, rear derailleur, cockpit junction box, and battery mount for simplified system setup.
  • Optimized for Performance & Engineering, this junction box supports smooth, precise electronic gear shifting and is compatible with Shimano Di2 electronic groupsets-enhancing overall drivetrain responsiveness.
  • A sleek, low-profile design that mounts conveniently underneath the bottom bracket shell, offering a clean aesthetic and improved aerodynamics, ideal for road, mountain, and gravel bike builds.
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We pride ourselves on our ability to ship and deliver your gear with excessive speed! We ship from 22 locations throughout the United States and most orders will arrive in 3 days or less with Free Shipping on orders over $75!

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Most orders placed during the workweek before 1:00 PM Eastern time ship the same day, but during peak/holiday season or depending on inventory location handling time can take up to 48 hours. If you have questions regarding shipping estimates, don't hesitate to get in touch with us before placing the order. There is a direct signature requirement for all orders over $500.

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365 Cycles puts the customer above everything. Our number one goal is your satisfaction. When you press the shift lever you want the gears to shift, and when you buy bicycle parts, you want the bicycle parts to arrive on time in new condition. With over 60,000 products and 22 warehouse locations throughout the country, we have the parts you need and they are coming in hot!

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Our team is waiting to help you 7 days a week and they are more qualified to help than I am but if you ever feel like you're not getting the service you need I’m personally asking you to email me at ben@365cycles.com with "CUSTOMER LOYALTY" in the title and I will personally handle your order.

Over the years we have served millions of satisfied customers and continue to serve many of them today. With your feedback, we are confident we can take this lifelong journey together and build a friendship that goes beyond parts and accessories.

“If you want to go fast, go alone, if you want to go far, go together.” -Someone Smart

Ben Berman Founder & CEO of 365 Cycles


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