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Quickshifter on BMW S1000RR motorcycle.

A quickshifter (or quick shifter) is a device that allows clutchless gearshift on a manual transmission, and is commonly used on motorcycles. It increases safety and comfort of the vehicle since it eliminates the need of adjusting the clutch or throttle before and after gearshift.[1] Since they eliminate the need of adjusting clutch and throttle during gearshift, they are quicker(usually shift in less than 50 millisecond) and also used as performance enhancement on motorcycles.[2]

Working mechanism[edit]

Almost all quickshifters work on the same basis, a sensor senses the gearshift action, a microcontroller (CPU) processes the data (and calculates the timing) and cuts off ignition momentarily, resulting in reduction of load at the transmission allowing the new gear to slip (and engage) into its place. However the method of sensing and reducing the load can vary.[1][2]


Most gearshift sensors work by measuring the pressure change (push or pull) on the shift rod. However, some sensors measure the molecular strain in the shift rod to determine the gearshift process instead of using a pressure switch. The use of molecular strain gauge (sensor) is costly but more reliable (than push/pull sensor) and free from false readings due to vibrations since it has no moving parts.


These CPUs generally control the ignition and/or fuel supply to reduce load from transmission when needed. They can be either separate from ECU or a single unit(ECU performing quickshifting). They can provide near-perfect gearshift in tens of milliseconds.

Load reduction[edit]

The load from transmission is generally reduced by cutting off the ignition and/or fuel supply in the engine, or by disengaging the clutch. Since load is reduced from transmission precisely (if tuned correctly) by microcontroller, it does less damage to use the quickshifter than clutchless gearshift without a quickshifter on a manual transmission.[3] This process is also called unloading.

Bi-directional quickshifter[edit]

The term bi-directional quickshifter means that the quickshifter works on both directions of gearshift - upshifts and downshifts.[4] Most quickshifters are bidirectional, so the term quickshifter is usually alone sufficient.

However, exceptions are present such as 2016 Kawasaki Ninja ZX-10R and 2015 H2/R's "KQS" quickshifters which are "mono-directional" and only work on upshifts.[5] Their primary aim is usually to achieve better acceleration by reducing the time interval between gearshifts during acceleration which results in continuous and smoother power delivery to the wheels.

Examples of performance oriented motorcycles using bi-directional quickshifter are BMW S1000RR and S1000R, 2017 Kawasaki Ninja ZX-10R and H2/R, Suzuki GSX-R1000/R, Aprilia Tuono etc.[6][7][8][9]


  1. ^ a b "Motorcycle Quickshifter: What They Are & The Best Options". Life at Lean. 2013-10-10. Retrieved 2017-09-26.
  2. ^ a b "How Do Motorcycle Quick Shifters Work? | RideApart". RideApart. Retrieved 2017-09-26.
  3. ^ "ASK KEVIN: Are Quickshifters Hard on the Gearbox?". Cycle World. Retrieved 2017-09-26.
  4. ^ "The 2017 Kawasaki ZX-10RR Is Race Ready". Cycle World. Retrieved 2017-09-26.
  5. ^ MacDonald, Sean. "The All-New 2016 Kawasaki ZX-10R Might Be The Fastest Street-Legal Japanese Bike Ever". Lanesplitter. Retrieved 2017-09-27.
  6. ^ "Suzuki Canada | The Motorcycle & ATV Show Moncton". monctonmotorcycleshow.com. Retrieved 2017-09-27.
  7. ^ "First Look: Inside the new 2015 Kawasaki Ninja H2". Sport Rider. Retrieved 2017-09-27.
  8. ^ "Kawasaki's Ninja H2 and H2R Go Even More High-Tech for 2017 (with video)". Sport Rider. Retrieved 2017-09-27.
  9. ^ "2016 Aprilia Tuono 1100 V4 RR - FIRST RIDE". Cycle World. Retrieved 2017-10-06.

See also[edit]

Motorcycle transmission

Electronic aids: