Shimano UN55 Bottom Bracket
Best reliable component for maintaining or upgrading older bicycles.
A reliable, no-nonsense upgrade for older drivetrain systems. This sealed cartridge unit offers exceptional longevity and smooth rotation, making it the go-to choice for keeping classic bikes on the road without constant maintenance.
$29.99
at
Diamond Cycle
Who it's for
- Everyday riders seeking a dependable, low-maintenance component.
- Budget-conscious cyclists and those performing routine bike maintenance.
- DIY bike mechanics and riders preferring hassle-free component upkeep.
Who should skip it
- Performance-oriented riders and weight-conscious competitive cyclists.
- Cyclists upgrading to modern drivetrains and those seeking the latest technology.
- Strong riders and competitive athletes demanding maximum power transfer.
Performance breakdown
Installation ease
Standard threading makes swapping this unit into most frames straightforward.
Weight efficiency
Hollow spindle design sheds grams without sacrificing necessary structural integrity.
Compatibility
The JIS square-taper standard remains widely compatible with classic and commuter setups.
Smoothness
Delivers a consistent, friction-free rotation that feels refined under heavy pedaling.
Build quality
Robust steel construction ensures this component outlasts most other drivetrain parts.
Longevity
Sealed cartridge bearings provide exceptional resistance against grit and moisture ingress.
Key Specs
Spindle Type
Square Taper
Thread Standard
English
Shell Width
68mm
Q-Factor
122.5mm
Spindle
Hollow
Crankset Compatibility
JIS Square-Taper
Shell Thread Type
English
Know before you buy
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Ask Metto anything about the Shimano UN55 Bottom Bracket before you decide.
