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What do you think of the 2 gear gear box, will it be more fun or less fun then..

Discussion in 'Roadster' started by danny, Aug 15, 2006.

  1. danny

    danny Administrator

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    a six speed. I for one like the idea of it because the point of gears is to keep maximum power but the roadster has it at all times.
     
  2. WarpedOne

    WarpedOne Supreme Premier

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    Not power, torque - "acceleration oomph" :)

    I have 6speed transmision and found it to much work. This 2-speed is much more like a very good automatic with two regimes - sporty and leisure.
     
  3. danny

    danny Administrator

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    I think the 2 speed will be interesting on the track, you basically never have to change.
    The cool thing will be that you never will mess up and be in wrong gear so every turn,
    you will have the right power if you wanna put the car in oversteer or whatever you want.
    IT will be great for beginners. I'll miss the skill of staying in the right rev range but now we
    can focus on precise steering and throttle amount instead.
     
  4. tonybelding

    tonybelding Active Member

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    It sounds way fun to me. In fact, the two-speed gearbox and lack of a clutch, along with the electric motor's torque curve and RPM range, make it sound like it should be *incredibly* fun to drive. Easy, sure. . . (Especially in town.) But at the same time, a bit more direct and involving than an automatic.

    By the way, grandma had a funny comment when she heard about the car only having two forward speeds. "It's just like our old Model T!"
     
  5. feelthesweetbeat

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    two gears would rock... i think it would be cool to see the video game "low" "high" on the shifter box. Honestly, whatever takes me around the track faster i like. I was a die hard rotary engine fan... well still am but damn this tesla really has made me rethink things... DAMN YOU TESLA!!! :) hate to love you
     
  6. Zoom

    Zoom Member

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    Re: What do you think of the 2 gear gear box, will it be more fun or less fun th

    I would have to drive the car in both gears to decide if it's well matched or if it needs more gears (please feel free to call me when the car is ready for testing ;D). I would think that a 6 or so geared transmission coupled to an electric motor with nearly flat torque throughout it's RPM range would add significant complexity, moving parts, weight, and would be a waste of money. After all, the transmission is necessary for two things: One, to get you rolling from a dead stop without stalling the engine (the clutch) and two, to keep the motor in it's optimal torque range so that you can get the power to the wheels efficiently. Granted, gearing is also a torque multiplier, but gears simply for the sake of shifting is a bad idea. What we really need is an infinitely variable transmission controlled by a computer, and add driver selected choices like maximum economy, performance, maximum range, or something like that. Of course, no shifting required may not fit with the image of a sports car.
     
  7. danny

    danny Administrator

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    Re: What do you think of the 2 gear gear box, will it be more fun or less fun th

    Very well said. Noise, and lots of gears are only part of sports car image because people are used to that helping the "normal sports car" but with tesla its irrelevant.
     
  8. feelthesweetbeat

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    Re: What do you think of the 2 gear gear box, will it be more fun or less fun th

    I had the thought about implementing a CVT (continuously variable transmission) option but with the torque curve being so flat up to 9000 rpm (i believe), it would be quite unnecessary. The main purpose of the CVT is to allow the engine to keep rpm's at peak torque which (especially for american cars) practically eliminate the drawbacks of a peaky engine. CVTs by design have more drivetrain loss and are unable to take much torque/rpm (thats why we see them on golf carts and medium power cars for now). If the torque is the same at all rpm and the motor can operate at 13000 rpm, itd be tough to show how designing a CVT would benefit over the 2spd (physical gears have the lowest transmission loss) or just even a solid shaft to a larger ratio diff.
     
  9. Michael

    Michael Member

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    Although the torque may be very flat, through a large rpm range, I wonder whether the energy usage would be the same regardless of the rpm that the electric motor is operating at. Could it be that the benefits of a CVT could be used as a way to help the EV provide the best power utilization for extended range driving, in addition to allowing extraordinary torque for PTO? The engine in the Tesla is no more powerful than several ICE vehicles that are currently using a CVT, so the CVT already exists to handle the power.
     
  10. WarpedOne

    WarpedOne Supreme Premier

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    CVTs are much less efficient than fixed gearboxes. Fitting one on electric motor would eat all savings one would hope to get from it and then some.
    And they are also much less durable.
     
  11. kevincwelch

    kevincwelch Active Member

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    Well, it isn't a functional gas station anymore. So, I guess I wasn't technically EVing anyone. :rolleyes:
     
  12. ElSupreme

    ElSupreme Model S 03182

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    Electric motors run basically the same efficiency (not enough different to really notice) in their full range. So you will use the same power regardless where you are in the speed curve. Adding a gearbox would only decrease efficiency, but you would get more top speed.

    But I don't really plan on going 125 in my car more than once, just to say I did it. 134 in my VW GTI was just stupid.
     
  13. mnx

    mnx 2013 P85

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    Looks like Kevin accidentally posted to the wrong thread and resurrected it after 7 years! lol
     

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