How does a Motorcycle Quickshifter work?

A quickshifter allows you to make clutchless shifts. Keeping the throttle pinned, clicking up and down the gearbox, saving you a few milliseconds and minimal loss of RPM each shift. Now a few milliseconds doesn’t sound like a lot, but when you are racing in MotoGP, it can be the difference between winning and losing over a few laps.

Why do you need a quickshifter?

To be honest, we most probably don’t. But what fun would that be, especially on track days or getting that buzz when you quick shift whilst blasting along your local back roads.

I don’t know about you but upshifts and downshifts with the “auto-blipper” on my KTM 790 Duke sound sweet, letting me play at being Rossi for a few seconds.

What are the mechanics of a quickshifter?

Quickshifters come in various forms and setups, depending on the application and manufacturer.

At their core, they cut the ignition spark or fuel injection just prior to the gear shift. This unloads the transmission, allowing the new gear to slip into place. This all happens in a fraction of a second (50 milliseconds), but is enough time to unload the transmission, allowing you to quickly shift either up or down.

The gear lever mechanism is fitted with a transducer, that reads the pressure applied to the shift rod. This transducer provides feedback to the bike ECU. When you change gear, this action is detected and tells the ECU to cut off the ignition spark or fueling, depending on the setup.

What is an auto-blipper?

When you downshift, you want the revs to rise, so the quickshifter electronics take care of this on the downshifts. Many riders do this naturally, they “blip” or rev match the throttle prior to a manual downshift, hence the name auto-blipper. This blipping action helps smooth out the speeds between the clutch and transmission, making for a smoother downshift.

What are the different types of quickshifters?

Most current motorcycles are fitted with a physical in-line switch on a rod, that is connected to the gear lever mechanism.

As the gear lever is moved up to select a gear, a spring compresses and the switch makes contact and sends a signal to the ECU, telling it you are about the shift. It is a simple design but has some inherent issues, the switch and spring can wear over time, it requires a positive gear selection by the rider, and the spring in the switch mechanism takes away some of the direct feel of shifting.

Switch Based Quickshifter
Switch Based Quickshifter

The other type of quickshifter available is based on a strain gauge detecting the gear shift. Currently, this is primarily used by race teams, due to the cost. The strain gauge setup does not wear and allows for a more direct feel when shifting. It’s also programmable, allowing mechanics and riders to make adjustments based on the pressure the rider needs to apply to the gear change mechanism in order to shift gears.

Switch Based Next to Strain Gauge Version (red)
Switch Based Next to Strain Gauge Version (red)

Can a quickshifter damage your gearbox?

Never say never, but it appears when you read riders’ experiences and reviews, it’s a very small chance of hurting your gearbox or transmission. The reward far outweighs the risk, so to speak.

Many riders say the smoother gear changes prolong the life of their gearbox.
Normally the edges of the shift dogs suffer less wear in a quickshifter setup.

Who sells aftermarket quickshifters?

Some popular quickshifter brands are Dynojet, HM Quick Shifters, and Bazzaz.

Any tips for first-timers using a quick shifter?

Keep the throttle pinned on the upshift and close it for the downshift.
Quickshifters tend to function better in higher gears, due to the gear ratio often being smaller as you move up the box into higher gears.