Conversion BB - Shimano Mountain
Best solution for installing Shimano cranks on non-compatible mountain bike frames.
Upgrade your mountain bike drivetrain with the Praxisworks Conversion Bottom Bracket. This essential component is engineered to seamlessly integrate Shimano mountain bike cranksets with frames featuring BB30, PF30, or OSBB shells. It provides a reliable and smooth-performing solution, whether you are building a custom bike from the ground up or looking to enhance your current setup. Trust this conversion BB for dependable performance on the trails.
$74.99
Owner Satisfaction
4.6
/ 5
Category Rank
417
/ 2104
#417 in Components
Price vs Category Average
-27%
Below average
Compatibility
Shimano Mountain Bike Cranksets
/ Shimano Mountain Bike Cranksets
Who it's for
- Riders tired of annoying bottom bracket creaks
- Cyclists upgrading to Shimano cranks on non-standard frames
- Mountain bikers riding in harsh, muddy conditions
Who should skip it
- Home mechanics lacking specialized tools or experience
- Weight-conscious racers chasing every gram of savings
- Budget-focused shoppers seeking a basic replacement part
Performance breakdown
Bearing Smoothness
High-quality seals ensure minimal drag for efficient power transfer on trails.
Installation Simplicity
The threaded design eliminates common creaking issues found in press-fit systems.
Frame Compatibility
Expertly bridges the gap between Shimano cranks and non-standard frame shells.
Structural Rigidity
Solid construction maintains drivetrain alignment under heavy pedaling loads.
Durability
Resilient materials withstand harsh trail conditions and frequent wash cycles.
Drivetrain Integration
Seamlessly adapts Shimano mountain components to diverse frame standards.
Key Specs
Compatibility
Shimano Mountain Bike Cranksets
Frame Shell Compatibility
BB30, PF30, or OSBB
Brand
Praxisworks
Model Number
73-3001
Features
- Enables Shimano MTB cranks on specific frames
- Ensures smooth and reliable operation
- Ideal for drivetrain upgrades
- Designed for custom bike builds
- High-quality conversion solution
What customers say
Customers overwhelmingly praise the Conversion BB for solving a critical compatibility issue, allowing Shimano mountain bike cranks to work seamlessly with Praxisworks bottom bracket frames. The core theme is exceptional reliability and quiet performance. Users appreciate that this converter eliminates the common creaking associated with press fit systems, offering a dependable, set it and forget it solution. The robust construction and precision engineering provide a solid feel, even during demanding mountain use. While installation requires specific tools, the consensus is that the superior longevity and peace of mind fully justify the investment over cheaper, less dependable alternatives. This product is highly recommended for its effective problem solving.
Know before you buy
Yes, this model is specifically engineered to adapt Shimano mountain bike cranksets to frames that use BB30, PF30, or OSBB shell standards.
Yes, the Praxisworks Conversion BB is designed to fit BB30, PF30, and OSBB shells, making it a versatile solution for converting those specific standards to accept Shimano cranks.
Yes, you will need a specific bottom bracket tool compatible with Praxisworks conversion systems to ensure the cups are seated correctly and securely in your frame.
Conversion bottom brackets like this one are designed to be more stable and reliable than simple press-in adapters, as they typically feature a threaded or integrated design that minimizes creaking and improves bearing alignment.
No, this specific model is optimized for Shimano mountain bike cranksets. You should check the Praxisworks catalog for road-specific conversion options if you are working on a road or gravel build.
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