The Shimano BB-MT501 R&L Threaded is a Hollowtech II external cup bottom bracket designed to connect Shimano MTB cranksets (with a 24mm spindle) to a bicycle frame with a BSA threaded bottom bracket shell.
It includes both the right and left bearing cups (R&L) and is part of Shimano’s Deore-level MTB drivetrain components.
This bottom bracket is commonly used on mountain bikes, gravel bikes, and trekking bikes.
Key Features
Genuine Shimano Hollowtech II external bearing system
Threaded BSA (English) installation
Compatible with 68mm and 73mm frame shells
Sealed cartridge bearings for improved durability
Smooth rotation and efficient power transfer
Improved sealing against mud, water, and dust
Works with Shimano 24mm crank spindles
Includes spacers for correct drivetrain alignment
Designed for MTB and trekking use
Specifications
Specification
Details
Brand
Shimano
Model
BB-MT501
Type
External cup bottom bracket
System
Hollowtech II
Thread Standard
BSA (1.37” x 24T)
Shell Width Compatibility
68mm / 73mm
Axle Compatibility
24mm crank spindle
Bearings
Sealed cartridge
Material
Aluminium cups + resin spacer tube
Use
MTB, gravel, trekking
Who Is It Suitable For?
Mountain bikers (XC, trail, light all-mountain)
Gravel riders using Shimano Hollowtech II cranks
Trekking and commuter cyclists
Riders replacing worn bottom brackets
Bike mechanics servicing Shimano MTB drivetrains
Riders with 68mm or 73mm BSA threaded frames
Who Should Use It?
Riders using Shimano Deore / SLX / XT Hollowtech II cranksets
Cyclists needing a reliable replacement bottom bracket
MTB riders wanting improved sealing and durability over older models
Riders experiencing creaking or rough pedal rotation
