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What Is Double Clutching, And Should You Be Doing It?

We’ve all seen the scene in The Fast and Furious where Brian O’Connor just lost his first race to Dom. Yet he is standing next to the car with a gigantic shit eating grin on his face. “I almost had you man!” Which incites laughter and mockery from street racing legend Dom. “Granny-Shifting. Not double-clutching like you should.” This has always been one of those famously cringe worthy quotes. In case you’re unfamiliar with the concept of double clutching the concept is simple. When executing a shift you follow these steps. #1, lift off the accelerator. #2, Depress the clutch pedal. #3, Shift out of gear into neutral. #4, Lift off the clutch pedal. #5, Re-depress the clutch pedal. #6, Shift into the desired gear, rev matching where necessary. #7, Release the clutch pedal. It is worth noting that this is a fluid process, many of the steps are happening together to form a seamless, smooth shift.

So why is this cringe worthy? Well, as any car guy will tell you modern cars have transmissions with synchros. Synchros make shifting much easier and much smoother. It allows for seamless meshing between the gears with reduced risk of grinding them. In the old days, the days before synchros you had to double clutch. So, and I hate to disagree with the all-knowing Dominic Toretto but your burn is incorrect. The glorious ignorant newb you will later call Mr. Arizona was correct in his chosen style of shifting.

So, just to be clear… If your car has a manual transmission in perfect working condition there is absolutely no need to double clutch.

In any rate if you are still unclear on the concept or just want to geek out on transmission tech talk watch the following video. The entire concept is explained by someone far smarter than I am.

Source: Engineering Explained on YouTube


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  1. Actually the problem with the quote is that they were racing. Double clutching when accelerating makes zero sense.

    However when downshifting, double clutching actually will increase the life of the synchros in the transmission. It also allows for more seamless rev matching.

    • Sometimes while racing a production type vehicle with a higher than stock redline, but still using the stock transmission, double clutching on acceleration is required. Why? Because the synchros are not designed to work at higher revolutions and cannot match fast enough.

  2. Commercial trucks (10speeds+) the transmissions don’t have synchros so double clutching is the prescribed method. The gears are typically spaced about 300rpm over lapped. So, in most trucks; getting to the high end of the sweet spot somewhere between 1500-1800 rpm clutch in, pull it out of gear, release the clutch, let the rpms fall to about 1300 clutch in, move to the next gear, release the clutch.

    When decelerating it works in reverse.

    From 10th, to 7th, clutch in, pull it out of gear, decelerate(coast or brakes) when you get to 7th gear speeds (in a truck that’s about 20-25mph) clutch in, bump the fuel to get the rpms up, drop it into gear and go.

    After a little while, it’s all smooth and you go from sweet spot to sweet spot seamlessly.

    Of course this is only the prescribed method. Most guys I know don’t bother with the clutch, the float the gears from high side of the sweet spot to low side of the sweet spot in the next gear. No clutch needed.

  3. Double-clutching is required with downshifting, to avoid locking the tires. Not doing it may cost you 0.1-0.5 seconds on acceleration after the curve.

    Double-clutching while accelerating is just a waste of energy and time. Not needed.

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