E‑Bike PAS Cadence Sensor SR‑PA112/121/131/142.32‑S, JIS Square Spline 68/73mm BSA Thread Bottom‑Bracket Sensor with G6.5.4 Plug

This integrated bottom‑bracket‑mounted PAS sensor is original‑spec spare replacement part for Bafang e‑bike pedal‑assist systems. It is cadence‑only speed sensor (measures pedaling rotation speed, does NOT detect pedaling torque). It outputs stable 32‑pulse signal per full spindle rotation for responsive pedal‑assist behaviour. Multiple variants are available for 68 mm and 73 mm BSA‑threaded frame bottom‑bracket shells.

✅ Matched Bafang e‑bike pedal‑assist controller & display system

✅ SR‑PA112.32‑S: 68 mm BSA‑thread bottom‑bracket shell

✅ SR‑PA121.32‑S: 68 mm BSA‑thread bottom‑bracket shell, short total spindle

✅ SR‑PA131.32‑S: 68 mm BSA‑thread bottom‑bracket shell, intermediate‑length spindle

✅ SR‑PA142.32‑S: 73 mm BSA‑thread mountain‑bike bottom‑bracket shell

✅ Multiple variants for 68 mm &73 mm BB shell

SR‑PA112.32‑S / PA121.32‑S / PA131.32‑S fit standard 68 mm BSA‑thread city / mountain‑bike frames; SR‑PA142.32‑S is dedicated for 73 mm threaded MTB bottom‑bracket. Different spindle lengths satisfy varied crank‑installation offset requirements.

✅ High‑precision 32‑pulse cadence‑only detection

Generates 32‑pulse signal output per one full spindle revolution. Provides fast and accurate pedaling‑rotation feedback for controller, delivering smooth, natural pedal‑assist response for commuting, hill‑climbing and trail‑riding. No torque‑measurement function.

✅ JIS‑standard 17 mm square‑hole spline spindle

Adopts industry‑standard JIS 17 mm square‑hole spline interface. Supplied with M8×1‑pitch‑25 mm‑length fixing screw for safe and firm crank mounting.

✅ G6.5.4 connector & two‑option outlet‑cable

Comes with G6.5.4 waterproof plug. Two cable‑length selections (150 mm / 950 mm) for different internal‑frame wiring‑routing needs.

✅ Wide working‑temperature range

‑20 ℃ ~ 60 ℃ operating range, guarantees reliable year‑round outdoor riding performance.

Product Name: Bafang PAS Cadence‑Only Speed‑Sensor (SR‑PA1XX.32‑S Series)

Full available model numbers: SR‑PA112.32‑S; SR‑PA121.32‑S; SR‑PA131.32‑S; SR‑PA142.32‑S

Function: Cadence‑only speed‑detection (no torque‑sensor)

Thread Standard: BC1.37″ * 24T (BSA inch‑thread)

Spindle Standard: JIS 17 mm square‑hole spline shaft

Signal Output: 32 pulses per full spindle rotation

Outer‑diameter(C): φ45.5 mm

Fixing Screw: M8×1 pitch, 25 mm length

Plug‑in Connector: G6.5.4

Outlet‑Cable Length: Optional 150 mm / 950 mm

Rated Input Voltage: DC 4.2‑5.5 V

Operating Temperature: ‑20 ℃ ~ 60 ℃

1 × Selected‑model PAS cadence‑only sensor (choose correct model & cable‑length)

1 × M8×1‑25 mm fixing screw