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SKU: CR3484

Shimano BB-UN300 Square Taper JIS Bottom Bracket | 68x113mm Hollow Spindle for BSA Cycling Frames, Seamless Integration with JIS Square Taper Cranksets, Durable Aluminum Construction, Black Finish for Road & Mountain Bikes

Regular price $15.43
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Description
Specifications

Upgrade your bike's performance with the Shimano BB-UN300 Square Taper JIS 68x113mm Bottom Bracket - the ideal choice for reliable and efficient power transfer on your ride. Crafted for durability and precision, this bottom bracket is designed to fit JIS (Japanese Industry Standard) square-taper cranksets, making it compatible with a wide range of road, mountain, and commuter bikes.

Materials & Engineering:

Constructed with a high-strength, hollow spindle for optimized weight-to-strength ratio, the Shimano BB-UN300 ensures long-lasting performance and smooth pedaling. Its robust aluminum or steel components are engineered for high resistance to wear and corrosion, providing dependable operation in various riding conditions.

Components & Technology:

Featuring a sealed bearing system, this bottom bracket minimizes dirt and moisture ingress, reducing maintenance needs and extending component lifespan. The square-taper interface ensures a secure fit with crankarms, delivering efficient power transfer with minimal flex or slip.

Style & Use Case:

With a sleek black finish, the Shimano BB-UN300 complements any bike aesthetic-from sleek road bikes to rugged mountain bikes. Its standard 68mm shell width and 113mm spindle length make it versatile for various frame sizes and styles, suitable for both recreational riders and serious cyclists seeking reliable performance.

Innovative Features & Benefits:

- Compatible with JIS square-taper cranksets for wide-ranging application use

- Hollow spindle design for lightweight strength and rigidity

- Sealed bearings for enhanced durability and reduced maintenance

- Easy installation with thread specifications optimized for BSA (English) threaded frames

Maximize your bike's efficiency, durability, and riding comfort with the Shimano BB-UN300 Square Taper Bottom Bracket - a trusted choice for cyclists demanding performance and longevity. Whether upgrading or building from scratch, this bottom bracket ensures smooth, reliable power transfer with every pedal stroke.

  • High-quality, durable construction with a hollow spindle design for enhanced weight savings and improved pedaling efficiency.
  • Engineered for compatibility with JIS square-taper cranksets, ensuring reliable power transfer and smooth rotation across various bike models.
  • Precision-machined from high-grade materials, the Shimano BB-UN300 offers superior durability and corrosion resistance for long-lasting performance in all weather conditions.
  • Designed with a 68mm shell width and 113mm spindle length, this bottom bracket provides optimized frame fit and enhanced stiffness for aggressive riding styles and commuting.
  • Easy installation with a BSA (English) bottom bracket shell interface, making it a versatile upgrade for road, hybrid, and mountain bikes that require a secure, seamless fit.
Bottom Bracket Shell I.D.1.37
BB/Frame InterfaceEnglish
BB Shell Width (mm)68
Spindle Interface TypeSquare Taper JIS
Spindle Length113
Defined ColorBlack
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Customer Reviews

Based on 36 reviews
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C
Colonel John

You must be sure of your bottom bracket size. You can get that from your bike specs. I found this BB bearing to be perfect for my bike. It was easy to install and solved the knocking I was getting from every pedal rotation. You must have the spline tool to remove your old BB bearing and install the new one.

C
Colonel John

You must be sure of your bottom bracket size. You can get that from your bike specs. I found this BB bearing to be perfect for my bike. It was easy to install and solved the knocking I was getting from every pedal rotation. You must have the spline tool to remove your old BB bearing and install the new one.;

S
Sean

Not too heavysmoothvery nice👌🏻👌🏻👌🏻;

M
Michael D Ramos

Thank you for the fast service. I have an older Trek Marlin 5. The bottom bracket I purchased is top quality easy to install and purrs like a charm with every crank hammering rotation. Thanks again.

M
Michael D Ramos

Thank you for the fast service. I have an older Trek Marlin 5. The bottom bracket I purchased is top quality easy to install and purrs like a charm with every crank hammering rotation. Thanks again.;