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Braking issues ...

Discussion in 'Roadster' started by letoufou, Feb 16, 2010.

  1. letoufou

    letoufou New Member

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    one week living with the roadster sport now ...

    very impressed by the handling, the immediate torque and the acceleration ... beeing used to sports car i was not waiting for such "push me in the back" effect.

    this car is definitly not a toy and at the red light you will smoke any 911 or F430.

    the most complain for me will be the brakes wich i found WAY TO LIGHT ...
    2 piston caliper in the front and 1 for the rear this is the same steup as for the "small" elise which has 800 lbs less weight to stop :eek:

    i find 2 issues :

    1/ brakes are not powerfull enough

    2/ ABS is coming WAY to early

    Question 1/ :
    did anybody upgraded the brakes ?
    i am thinking of installing AP racing 4 piston calliper front + Rear (same as EXIGE CUP) but i do not know if they will fit ... any advice :confused:

    Question 2/ : i know it is possible to enter an "administrator" menu and have access to "hidden" options ... do you know how to do it and if it is possible to disable the ABS ?
    (except on the wet i quite always disable the traction control which i find also annoying ...)

    PS yes i live in Europe where you can still have fun on small mountainous roads without ending up in jail like in the US :biggrin:
     
  2. vfx

    vfx Well-Known Member

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    I know the Lotus aftermarket suppliers like Sector111 sell better brake pads.
     
  3. ChargeIt!

    ChargeIt! Member

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    Are you sure you mean ABS or do you mean T/C comes on way too early ? (The Traction Control is HUGELY more complicated on an EV with regen in general as compared to an ICE. The Tesla in particular is sensitve because it is conservative ...) Are you using winter tires, and what are they ?
     
  4. elirentz

    elirentz Member

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    well if you're engaging ABS too early your tires are the problem any upgrade to the applied braking force is just going to cause ABS to engage that much more quickly.

    As far as fitment goes I would imagine if the calipers are the same anything that will fit on the elise should work. I'm sure there are plenty of aftermarket big brake kits for the elise.

    I would think that upgraded pads, ss brakelines, and better tires would be all the upgrade you would need short of serious track duty.
     
  5. mpt

    mpt Electrics are back

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    Hmm, IMO the tires on the Sport are about as sticky as they get on a reasonable road car; they're very much summer tires though; might be a little cold for them at this time of year - assuming you're north on the equator!

    For me I have to say... brakes, do we have those, I don't recall using them :biggrin:

    I was on the local highway doing some miles-per-hour after passing a group of cars when I did need to slow down I did feel the car skip a bit and was surprised a little but put it down to simply getting more feedback than I'm accustomed to.
     
  6. ChargeIt!

    ChargeIt! Member

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    Yes, letoufou says he lives in Europe, which is why I asked about the winter tires.

    I am pretty sure what you felt was not ABS, but the sensitive T/C software during regen, probably when experiencing a change of surface (bump, crack, etc). (That being the reason for my first question to letoufou.)
     
  7. vfx

    vfx Well-Known Member

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    A lot of reviews of the Roadster in magazines and video. Not too many have mentioned the brakes as lacking.
     
  8. mpt

    mpt Electrics are back

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    It definately wasn't abs, but felt like the grip fading as the car flew over the broken and cracked surface; this is NJ, I imagine it to be similar to the moon. I'm trying to think if I saw the TC light come on or not. Does the force of the regen change as you brake or is it simply on/off based on grip?
     
  9. ChargeIt!

    ChargeIt! Member

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    #9 ChargeIt!, Feb 17, 2010
    Last edited: Feb 17, 2010
    Force of regen does not change when you touch the brake -- under normal circumstances. **BUT** if an event occures that "offends" :rolleyes: the sensitive T/C (the T/C light will blink) then the regen is affected (reduced), sometimes dramatically, i.e. possibly completely, i.e. ZERO regen, which is a VERY ODD feeling because you are now coasting with 85%+ efficiency, i.e. almost no deceleration. The only way to reproduce this consistently for your car is to charge completely, and maybe even top-off, in Range Mode. Be prepared, though, you'll have NO regen (for a dozen+ miles). ( But I think you know this, since you posted about absence of regen when battery is cold. )

    Edit: if "loss of grip" happened without regen (i.e. you were not decelerating) ... it is the T/C reducing power to the motor (i.e. power to the wheels). Although a slippage condition ("loss of grip") may or may not have actually occured, the T/C is so conservative and sensitive (compared to other cars, IMHO), it reduces power if slippage is imminent, then re-applies power an instant (milli-seconds) later; this you might feel as a "loss of grip" when it's just irregular surfaces.
     
  10. letoufou

    letoufou New Member

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    After turning the key (and beeing told tu unarm vehicle grrrr) the first thing i do it disengaging the TC ...
    But anyway as far as you brake in line...TC is not involved.

    Regarding the lack of power of the brakes...The problem is that the brake are those of the small elise...all other more performance cars are fitted with 4 pistons calliper F and R...instead of 2 and 1 on the roadster which is 1.000lbs heavier !
    Did anybody here upgraded the brake ? Should i put elise S1 or S2 calliper?

    Regarding the abs issue...temperature was just above freezing so yes it is more a thermocontact issue...i will tell you as soon as the weather will improve...but still do you know how to disconnect abs ?

    Ps i am not a crazy guy wanting to kill myself...it is just that i am used to drive a caterham CSR...and i am not used to have the car interfering in my driving ;-)
     
  11. mpt

    mpt Electrics are back

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    You really are driving it to the extreme!

    I don't know about the brakes but I do know that the disks are not the same as the regular Elise; they have a five hole bolt pattern so you'd need to investigate.

    I'm sure that the ABS could be disabled with some thought too - fuse pulled perhaps... Top Gear managed to do it... "How hard could it be?"

    Have fun!
     
  12. Webbie

    Webbie Rather Senior

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    Brakes better than they feel?

    I agree that the brakes don't feel as though they are as positive and quick to stop as some cars, but they may be better than they feel. According to Road&Track testing a Tesla stopped in 119 feet from 60 and 210 feet from 80. Not wonderful, but not the lowest of sports cars and better than all the sedans (I think).

    For instance, from 60 from 80
    Tesla 119 210
    Cayman 111 195
    MINI 121 210
    Saleen 119 210
    BMW M3 Coupe 116 205
    Exige 112 196
     

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