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SKU: CR3496

Shimano BB-UN300-K Square Taper JIS Bottom Bracket 68x127.5mm Hollow Spindle, English Thread, Compatible with Chain Case & JIS Cranksets, Durable Steel Construction, Black Finish for Road & Commuter Bikes

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Description
Specifications

Upgrade your bicycle's performance with the Shimano BB-UN300-K Square Taper JIS 68x127.5mm Bottom Bracket - a reliable and durable solution designed for seamless power transfer and bike longevity. Engineered for cyclists seeking compatibility with chain case setups and JIS square-taper cranksets, this bottom bracket offers optimized engineering for enhanced ride quality.

Materials & Construction:

Built with a hollow spindle, the Shimano BB-UN300-K features lightweight yet robust construction crafted from high-quality materials that ensure durability and corrosion resistance. Its black finish not only offers sleek aesthetics but also added protection against environmental elements.

Performance & Engineering:

Designed specifically for chain case compatibility, this bottom bracket provides smooth rotation and efficient power transfer. The hollow spindle minimizes weight without sacrificing strength, making it an ideal choice for urban commuters, touring cyclists, and leisure riders aiming for reliable performance across varied terrains.

Components & Technology:

Utilizing precision-engineered JIS square-taper interfaces, the BB-UN300-K guarantees a secure fit with compatible cranksets. The 68mm shell width and 127.5mm spindle length ensure perfect compatibility with a wide range of bicycle frames, while crankarm fixing bolts (sold separately) allow for customizable, secure attachment.

Style & Use Case:

Designed for classic bicycle setups, this black bottom bracket complements traditional and vintage-style bikes, making it perfect for restoring or maintaining city bikes, commuter bikes, and touring bikes. Its straightforward design and durable build make it a dependable choice for everyday cycling and long-distance adventures alike.

Innovative Features:

- Hollow spindle reduces overall weight for improved cycling efficiency

- Easy installation with standard JIS square-taper interface

- Compatible with chain case systems for a cleaner, more protected drivetrain

Key Specifications:

- Bottom Bracket Shell I.D.: 1.37 inches (English)

- BB Shell Width: 68mm

- Spindle Length: 127.5mm

- Spindle Interface: Square Taper JIS

- Material: High-strength steel with corrosion-resistant coating

- Color: Black

Optimize your bike's drivetrain with the Shimano BB-UN300-K Square Taper Bottom Bracket - a perfect blend of durability, reliability, and classic design for everyday cycling. Shop now for improved performance, easy installation, and long-lasting ride quality.

  • High-quality, rust-resistant steel and durable materials ensure long-lasting performance for everyday cycling and touring applications.
  • Designed specifically for JIS square-taper cranksets with 68mm shell width, providing a secure and reliable fit for a variety of bicycles.
  • Innovative hollow spindle technology reduces weight without sacrificing strength, enhancing overall cycling efficiency and power transfer.
  • Perfect for bikes with chain cases, this bottom bracket offers optimal compatibility and smooth operation in protected drivetrain setups.
  • Sleek black finish and precise engineering make this bottom bracket an ideal choice for style-conscious riders seeking reliable performance and easy installation.
Bottom Bracket Shell I.D.1.37
BB/Frame InterfaceEnglish
BB Shell Width (mm)68
Spindle Interface TypeSquare Taper JIS
Spindle Length127.5
Defined ColorBlack
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Ben Berman Founder & CEO of 365 Cycles


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