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SKU: CR3486

Shimano BB-UN300 Square Taper JIS Bottom Bracket | 68x117.5mm Hollow Spindle, BSA/English Threaded Bike Bottom Bracket for Cruiser, Road, & Mountain Bikes, Durable Steel Construction, Compatible with Square Taper Cranksets

Regular price $15.43
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Description
Specifications

Upgrade your bicycle's performance with the Shimano BB-UN300 Square Taper JIS Bottom Bracket - the perfect choice for reliable, smooth power transfer and durable long-lasting operation. Designed for compatibility with JIS square-taper cranksets, this high-quality bottom bracket features precision engineering and innovative materials optimized for both casual and competitive cycling.

Materials & Construction:

Constructed with a robust hollow spindle, the Shimano BB-UN300 ensures lightweight performance without compromising strength. Its corrosion-resistant black finish further enhances durability, making it ideal for various riding conditions. Made with high-quality materials adhering to strict manufacturing standards, this bottom bracket delivers longevity and consistent operation.

Performance & Engineering:

Engineered for seamless integration with 68mm wide BSA/English threaded frames, the BB-UN300 offers a precise fit that reduces wear and sloppiness. The hollow spindle design reduces weight, enhancing cycle efficiency and rider agility. Its smooth-bearing surfaces and high-quality bearings minimize friction, allowing for a more efficient transfer of power from pedal to wheel, boosting your ride's responsiveness.

Components & Technology:

Featuring a secure JIS square-taper interface, the bottom bracket provides a dependable connection with cranksets, ensuring minimal flex and maximized power output. Internal bearings are engineered for longevity and smooth operation, even under high torque and demanding conditions.

Style & Use Case:

With a sleek black finish, the Shimano BB-UN300 complements a variety of bike styles-from road and mountain bikes to commuter cycles. Its straightforward, tool-friendly design makes installation and maintenance accessible for both professional mechanics and DIY enthusiasts. Ideal for replacement or upgrade projects, it ensures your bike performs at its best on daily commutes, weekend adventures, or competitive races.

Key Features & Innovative Benefits:

- Compatible with JIS Square-Taper Cranksets for versatile use

- Hollow Spindle for lightweight performance and durability

- Precise 68x117.5mm shell and spindle dimensions for secure fit

- Designed for 1.37-inch shell I.D. frames with English/BSA threading

- Black finish for corrosion resistance and aesthetic appeal

Optimize your bike's drivetrain with the Shimano BB-UN300 Square Taper JIS Bottom Bracket - engineered for dependable performance, easy installation, and long-term reliability. Whether upgrading your existing setup or building a new ride, this bottom bracket provides the perfect foundation for smooth, efficient cycling.

  • Durable and lightweight hollow spindle construction enhances power transfer and reduces weight for optimized cycling performance.
  • Designed specifically for JIS square-taper cranksets, ensuring a secure and reliable fit for a wide range of road and mountain bikes.
  • Standard BSA/English bottom bracket shell interface with a 68mm shell width provides compatibility with numerous bike frames, simplifying installation and maintenance.
  • Precision-engineered for smooth rotational performance, this bottom bracket features high-quality materials and components to minimize friction and increase longevity.
  • Sleek black finish offers a classic look that complements various bike styles, making it an ideal choice for riders seeking durability, performance, and style in their cycling setup.
Bottom Bracket Shell I.D.1.37
BB/Frame InterfaceEnglish
BB Shell Width (mm)68
Spindle Interface TypeSquare Taper JIS
Spindle Length117.5
Defined ColorBlack
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Customer Reviews

Based on 3 reviews
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A
Amazon Customer

It fits as expected.

C
Customer

It fits as expected.;

週末DIY

Khodaa Bloom Rail Discの車載BBから交換。
完成車組の3枚クランク(メーカー不明)×全長110mmはチェーンステーとクランクが干渉した。干渉量は1mm程度。そのため、同仕様の118mmを使用。
その後、シマノRS200の2枚クランクセットにした際は、110mで問題なく装着できた。
製品精度は問題なく、特に違和感なく装着できた。;