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Is it OK to switch gears before coming to a complete stop?

Discussion in 'Model S' started by Torpedo Ted, Mar 23, 2015.

  1. Torpedo Ted

    Torpedo Ted Member

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    Will driving forward at a slow speed, and then chaning to reverse while still rolling slowly forward damage the gearbox or anything? How about doing it at faster speeds? Are there systems in place that makes sure it won't damage anything?

    And how about launching from a stand still - is it a good way to launch by putting the car in neutral, press pedal to the floor, and then set it to drive?
     
  2. dsm363

    dsm363 Roadster + Sig Model S

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    The car would protect itself. Are you doing this on purpose or do you mean if you accidentally bump gear selector?

    For launching the car you don't have to do anything other than have it in drive then push the pedal down.
     
  3. krisg81

    krisg81 Member

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    I rev it up to 10K RPMs in Neutral then drop the hammer into drive all the time, its a great alternative to Launch Control, thats for sure ;)
     
  4. billarnett

    billarnett Member

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    That' no problem at low speed; I do it every time I back out of my garage. But I think it only works below 5 mph or so.

    Just put it in D and step on it :)
     
  5. mikeash

    mikeash Active Member

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    I tried this and it doesn't work. The car wouldn't "shift" out of neutral until I pushed the brake. Kind of too bad, because that would be pretty cool.

    The PRND selector is purely software. You're just manipulating a joystick to tell the car what you want, basically. If you tell it that you want something it doesn't want to give you at the moment, all it'll do is refuse. The gearbox has a single gear and nothing ever changes there, all this does is change how the electrons go to the motor.
     
  6. FLDarren

    FLDarren Member

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    The car won't let u switch from D to R or R to D above 5 mph. I tend to back in almost wherever I park. This comes in handy as I almost never have to touch the brake pedal when I'm switching gears and backing into a parking place until I come to a stop.
     
  7. Brass Guy

    Brass Guy Member

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    Also if you're coasting in the opposite direction (my street and driveway slope slightly down, so I've backed in while still in D) you get regen when you use the accelerator.
     
  8. scottm

    scottm Active Member

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    huh?
     
  9. ChadS

    ChadS Petroleum is for sissies

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    As fldarren notes, the car won't let you do it if you are going fast enough that it will be a problem.

    The last Roadster firmware update changed the limit. I can't remember the exact numbers; but it raised it from somewhere in the 1-2mph range to somewhere between 2-5mph. They make very few Roadster firmware updates so they must have felt very comfortable making that change.
     
  10. billarnett

    billarnett Member

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    Say you are on a hill facing uphill with the car in D. Let it roll backwards a bit. Now press the right pedal (the accelerator). You will see the power meter show regen. There is some doubt as to whether this is really putting energy back into the battery or is just a software bug.
     
  11. martinwinlow

    martinwinlow Member

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    Oh, I reckon it's real, all right. What is the difference between this scenario and the 'normal' one when you ease up on the accelerator to slow the car down going forwards (using regen)?
     
  12. slcuervo

    slcuervo Member

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    I tested this some time ago. With the car stopped, I let it roll down the street with R on, and when driving at some speed (can't remember how much, but cerainly above 5 mph) I stepped on the accelerator to increase regen. And I remember clearly that it did "brake" harder, i.e. increased regen.

    I just tried it for 25-30 m, and then switched to D and kept driving. Not something I would often do on purpose (well, in fact I've never done it again).
     
  13. Footbag

    Footbag Member

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    The car wash I frequent uses the conveyor system (car in neutral). When it ends, the car is still coasting forward. Rather than coming to a stop only to start again, I've begun lightly touching the break (so light that it doesn't do anything, other than apparently register that it is engaged) and then shift to D, allowing me to drive away in a smooth fashion.
     

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