Technical entry
Idler Pulley
An idler pulley is a passive drivetrain component that redirects a bicycle chain without changing the selected gear ratio. […]
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Components
Individual parts, interfaces, and standards across drivetrains, brakes, wheels, suspension, and cockpit hardware.
21 technical entries
Technical entry
Power Meter
A cycling power meter measures the mechanical power a rider produces and reports it in watts. Most systems determine […]
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Oval Chainring
An oval chainring is a non-round chainring that changes the drivetrain’s effective gear ratio as the cranks rotate. Its […]
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Universal Derailleur Hanger (UDH)
The Universal Derailleur Hanger (UDH) is a standardized frame and hanger interface introduced by SRAM in 2019. It gives […]
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I-Spec
I-Spec is Shimano’s family of integrated handlebar mounts for attaching a compatible shifter or electronic switch to a brake […]
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Direct Mount Chainring
A direct-mount chainring attaches to a dedicated interface on the crank without using a separate bolt-on spider and conventional […]
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Narrow-Wide Chainring
A narrow-wide chainring uses alternating tooth widths that correspond to the alternating inner and outer links of a bicycle […]
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Head Tube Standards
Head tube standards define how a bicycle frame, headset, and fork steerer fit together. Compatibility depends on the frame’s […]
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Thru-Axles
A thru-axle is a removable wheel-retention component that passes through closed openings in a bicycle frame or fork, through […]
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