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Close call - ABS?

Discussion in 'Roadster' started by Mitrovic, Feb 15, 2011.

  1. Mitrovic

    Mitrovic Member

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    Today I had a "close call" when driving my roadster.
    It was on a wet road, I was driving around 80 Km/h in a light curve to the left. I saw a moped ( little motorcycle ) coming on a little street from the right. It is a strange intersection with a little wall between the roads. I saw the motorcycle not slowing down and I pushed the horn. At that moment the driver of the motorcycle turned his head and started breaking. But his motorcycle stopped in the middle of my lane! I did push the brakes hard, but there was no way I could stop, so I also turned the wheel. But with the famous understeer it seemed that the car would not turn, I think I softened the brakes and there the car turned and I missed the motorcycle by some centimeters. The car was then easily balanced, and I was happy to continue.

    I wonder where was the ABS? I did not feel any ABS "pumping" on the brakes. Does the ABS feel differently on the Tesla? Has anybody any experience with it?

    That is why I'm going on the track in march. It is a fast and capable car, but I still do not know its limits and I'm going to exercise!

    Why did this happen? I think that we have to keep in our mind when driving our cars, that the car is silent, the car sits low ( here the wall might have hidden the car from the view ), and the car can accelerate faster then the others anticipate! So be careful!
     
  2. WarpedOne

    WarpedOne Supreme Premier

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    ABS only engages to prevent wheels from blocking.
    You didn't push hard enough to block the wheels hence no ABS intervention.
     
  3. mpt

    mpt Electrics are back

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    I've triggered the ABS, it's really smooth.
     
  4. cinergi

    cinergi Active Member

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    The ABS in the roadster feels and sounds like ABS in any other car I've experienced it in. It does take a significant amount of pedal force (even on wet roads) to cause enough braking force that the wheels would otherwise lock up without ABS.
     
  5. doug

    doug Administrator / Head Moderator

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    Does an ABS event go into the vehicle logs? Is it something you could look up?
     
  6. cinergi

    cinergi Active Member

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    The Drive1s record appears to have this information in the b20/tc/abs field ...
     
  7. felixtb

    felixtb RsEU502,Sp+14274,XpEUSig4

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    I am sure if you have a near miss you press the brake as hard as it goes with out panicking. so I suspect the pressure was probably there. good query though. see if some one can find the logg. maybe ask they guys whom are doing the graphic parser....

    felix b.
     
  8. SByer

    SByer '08 #383

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    The Roadster has a really small vacuum assist pump. It takes a lot more pedal pressure than you think to really dig into the friction brakes. Take the car to a parking lot, best on a wet day, and try it. It's kind of surprising, but OK once you know.
     
  9. felixtb

    felixtb RsEU502,Sp+14274,XpEUSig4

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    I haven't gotten mine yet! just hyposezising based on other sports cars performance when it comes to brakes, even ceramic brakes which are notoriously hard to press before anything happens, different dynamics I know but still.

    but I will follow your suggestion once I have mine but probably on a track.........

    felix b.
     
  10. Mitrovic

    Mitrovic Member

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    Of course it is difficult to say what you really have done, because everything happens too fast to think. I certainly intended to press as hard as I can, and as I'm an "oldtimer-guy" I'm used to press the brake pedal very hard....Anyway I did not notice any ABS effect, but again may be I was just too focused on missing this motorcycle, so I did not notice.
    That's why I'm going to the track to test...

    How long is the log? I mean how far back does it stay saved?
     
  11. suxxer

    suxxer ElektroVolt

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    Just floor the brake at 50km/h - that's enough to hear the ABS working.
     
  12. n8te

    n8te Member

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    Good idea to hit the track. Anti-roll bars and suspension are meant to be adjusted to balance understeer/oversteer and it works exceptionally well on the Tesla. My guess is that the front tires just slid sideways (did not lock) because of the wet road. Since you were hard on the brakes, you had the front tires loaded, so I doubt you would understeer that much if the road were not slick. I find that fresh snow or rain on large, empty parking lots to be the best practice venues for handling.
     
  13. Mitrovic

    Mitrovic Member

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    I think you are correct n8te (?) Yes, I think that is what happened!
    I did press the brakes, but the wheels did not lock ( yet ) and the car began to slide and when I saw that I will not make it like that, I released the brakes a little bit - that is why ABS did not interfere - and that is when the car reduced the sliding and got around the motorcycle.
    I'll have the Tesla Technician look at the anti-roll bars and the suspension this week ( new firmware, too ), and then I will see how it reacts on the track. It will not be a race on the track, it will be just a training.

     
  14. tomsax

    tomsax Member

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    The detailed part of the log, where an ABS event would be recorded, covers about 60 hours of your most recent driving. The permanent section has one record per day (plus the occasional error record) and has enough room for many years of records.
     

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