Frisco E-Bike
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Pedal Assist Sensors

12-Magnet Cadence PAS Sensor, Dual Hall (generic)

The 12-magnet cadence sensor is the standard pedal assist pickup on hub-motor kits: a magnet disc that slides onto the crank spindle and a small sensor bracket that mounts against the bottom bracket. Dual-hall versions sense pedaling direction, so assist stops when you back-pedal. Twelve magnets give faster response than the old 5- or 8-magnet discs. Most use a 3-wire lead with either a Julet waterproof plug or a small SM plug. Installation is the fiddly part: the crank usually has to come off, and on some bikes the disc needs to be the split type.

Replacing a broken or intermittent PAS disc on a kit bikeUpgrading a slow 5-magnet sensor to 12-magnet responseBuilders who want assist to cut when back-pedaling

Current price and availability are shown on Amazon.

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Key considerations

  • Left-side and right-side mounting versions exist; match your original
  • Split-ring discs avoid pulling the crank but are less robust
  • Sensor gap should be about 2–3 mm from the magnets
  • Check connector type (Julet 3-pin vs SM plug)

Pros

  • Quick assist response
  • Direction sensing on dual-hall versions
  • Inexpensive

Considerations

  • Crank removal usually required
  • Fragile plastic disc
  • Connector variants

Compatibility notes

  • Standard 3-wire PAS inputs on KT and generic controllers — verify side, connector and spindle diameter

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Replacement parts

Confirm fitment on your bike before ordering — see each part’s compatibility notes.

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KT 36V/48V 22A Sine Wave Controller

KT (Kunteng) controllers are the de facto standard in the conversion-kit world, and the 22A sine wave unit is the one most people end up with for a 500W–750W hub motor. Sine wave drive is quieter than square wave and smoother off the line. KT controllers talk a specific serial protocol to KT displays (LCD3, LCD8H and friends), so if you already have a KT display this is the natural match; if you have a different display, plan to replace both. Connectors are typically the Julet/Higo waterproof style, which makes wiring tidy but ties you to matching plugs.

Best for: Replacing a dead controller on a KT-based conversion kit · Upgrading a noisy square wave controller to sine wave · Pairing with a KT LCD display

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Hands-on bike repair work
Pedal Assist Sensors

8-Magnet Split-Ring PAS Sensor (generic)

The split-ring cadence sensor exists for one reason: it clips around the crank spindle without pulling the crank arm off, so it is the easy-install option for riders without a crank puller. The magnet disc splits in two and screws back together, and the sensor mounts on a bracket against the bottom bracket shell. With 8 magnets the response is a touch slower than a 12-magnet disc, but for neighborhood riding you will rarely notice. It is a solid fix for a broken PAS disc when you want the job done in fifteen minutes.

Best for: Riders without a crank puller · Quick PAS repairs on kit bikes · Frames where the standard disc does not clear the chainring

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Sold on Amazon

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