TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

Summer Tire replacement - stay with 21", or drop to 19"

Discussion in 'Model S: Driving Dynamics' started by dj905, Aug 21, 2014.

  1. dj905

    dj905 Member

    Joined:
    Jan 16, 2010
    Messages:
    182
    Location:
    GTA, Canada
    My 21" summer tires are worn out (again), and I am trying to assess the options:
    - stay with 21" Continentals
    - switch to 21" Michelin
    - switch to 21" Hankook
    - drop down to 19" Michelin PS3 or AS3 with T-sportline wheels

    There are several questions in my mind:
    1. Cost? How much better is the tread wear with 19" performance tires over 21"?
    2. Performance? Am I likely to notice much performance difference if I go with 19" performance tires?
    3. Are the T-sportline wheels less susceptible to curb rash?

    The simple answer seems to be.. just stay with the 21" Continentals... is that the best answer? Fortunately, all four of my tires need to be replaced, so I can more easily make a change this time.

    David
     
  2. Gizmotoy

    Gizmotoy Active Member

    Joined:
    Sep 16, 2013
    Messages:
    3,137
    Location:
    Bay Area, CA
    Cost is difficult because obviously you have to factor in that if you go to 19"s you're buying new wheels. You'll save money on tires, but whether you make that cost back or not will depend on how long you keep the car. The tread wear should be similar between the 19"s and 21"s given identical tires. There's nothing inherent to the 21" size that's resulting in increased tread wear, it's the combination of rear camber/toe (also present when running 19"s) and soft compound tires.

    The contact patch of the stock 19" sizing is actually slightly larger than that of the 21"s, but that will be offset by the flex in the increased sidewall height. Further, the contact patch on the 19"s is longer and narrower, and length of the patch is one of the primary factors in rolling resistance. The difference is small, but given equal tires you may see slightly reduced economy on the 19" version. I suspect in anything but aggressive track use you'll notice no discernable difference between the 19"s with summer tires and the 21"s with summer tires.

    T-sportline's wheels will be less susceptible to curb rash simply because of the larger sidewall height. The larger the sidewall, the less likely curb rash becomes. They won't be immune, if that's what you're looking for, though.

    If I had the 21"s and was looking for a high performance summer, I'd be looking at Michelin's Pilot Super Sports over another set of the Continentals.
     
  3. omarsultan

    omarsultan Active Member

    Joined:
    Jun 22, 2013
    Messages:
    1,496
    Location:
    Northern California
    I believe treadwear is going to be more of a function of the tire compound than the size - check the UTQG ratings of the tires to give you a rough estimate of how they will wear (note the keywords there are "rough estimate).

    In terms of performance, depends on how hard you drive and how attuned you are. In theory 19" wheels are faster of the line than 21" wheels because they have less rotational inertia--I the real world, I am not sure if the difference is material or noticeable. The 45-series tire on the 19" wheel will have more sidewall flex than the 35-series tire on the 21" wheel, which, in theory, will make a difference in cornering. Again, it will come down to how hard you drive it and how attuned you are to the car.

    O
     
  4. jkirkebo

    jkirkebo Model S P85+ VIN 14420 EU

    Joined:
    Jun 13, 2010
    Messages:
    950
    Location:
    Fredrikstad, Norway
    Several owners in Norway have switched from 21" Contis to 21" Michelin PS2 and have reported two to three times the mileage per set compared to the Contis.
     
  5. Zextraterrestrial

    Joined:
    Mar 11, 2010
    Messages:
    3,636
    Location:
    Humboldt/Los Altos
    Personally like 19" better than 21" in every sense besides the look. quicker and better handling + better wear
     
  6. AndreyATC

    AndreyATC Member

    Joined:
    Dec 19, 2013
    Messages:
    380
    Location:
    NY, USA
    If you go aftermarket, might as well drop to 20, not to 19s
    You could get PSS tires with better 255/285 sizes
    I just did this and my car transformed into amazing sports car
    The amount of grip is endless
     
  7. linkster

    linkster Member

    Joined:
    Apr 22, 2013
    Messages:
    989
    Location:
    USAX2

    Say......have you entered your ballot to show TSportline the demand for 20" turbines?


    Do You Want TSportline to Produce 20 Turbine Wheels?
     
  8. AndreyATC

    AndreyATC Member

    Joined:
    Dec 19, 2013
    Messages:
    380
    Location:
    NY, USA
    No, but I do feel that 20 inch is perfect wheel size for this car, especially with just a tad wider rubber

    Here is my 255/285 PSS on Vorsteiner rims
     

    Attached Files:

  9. linkster

    linkster Member

    Joined:
    Apr 22, 2013
    Messages:
    989
    Location:
    USAX2
    Awesomeness light, strong, 20 forgies!
     
  10. LuckyLuke

    LuckyLuke Model S P85DL

    Joined:
    Dec 14, 2011
    Messages:
    2,092
    Location:
    Eindhoven, The Netherlands
    You don't use the brakes a lot, do you? ;)
     
  11. AndreyATC

    AndreyATC Member

    Joined:
    Dec 19, 2013
    Messages:
    380
    Location:
    NY, USA
    Nah, my car just happened to be sitting there for a few days, while we were on vacation
    Maybe i should have driven it before snapping pics
    LOL
     
  12. Liz G

    Liz G P03056

    Joined:
    Apr 16, 2012
    Messages:
    799
    Location:
    Wentzville, MO
    Here is a picture of Lithie with the mat black T-sportline 19's.

    IMG_20140809_190956[1].jpg
     
  13. mknox

    mknox Well-Known Member

    Joined:
    Aug 7, 2012
    Messages:
    8,561
    Location:
    Toronto, ON
    He likely just washed the car. I can watch my brakes turn that color right before my eyes as I wash/rinse the rims in my driveway.

    EDIT: Saw the post about it sitting. Mine will do that too if it's humid.
     
  14. bigdomer

    bigdomer Member

    Joined:
    Feb 17, 2014
    Messages:
    167
    Location:
    Franklin, TN
    As Gizmotoy said, I will be going with the Pilot SS's. Had those not come out in the proper fitment for the 21's, I would have ordered the 19's.
     
  15. linkster

    linkster Member

    Joined:
    Apr 22, 2013
    Messages:
    989
    Location:
    USAX2
    a) stay with 21"
    b) drop to 20"
    c) drop to 19"

    I am going with AndreyATC's answer: a definite "b".

    Maybe someday, my favorite car, built by my favorite employees, run by my favorite CEO will stop offering heavy, damage prone, alignment sensitive, gorgeous 21's as an option and instead offer 20" turbines. Tesla could still sell 21" turbines as an accessory item to owners that don't mind the extra expense (i really wanted to say, "have money to burn") on a 21" wheel/tire combination.
     
  16. Blathering1

    Blathering1 Remember

    Joined:
    Sep 16, 2013
    Messages:
    113
    Location:
    USA...Carolina...Chapel Hill
    The prone to damage is the real bell ringer against the 21's.

    While some road craters will impact a 19, 20, and 21, a minor road impediment will damage the 21 tires, and likely the rims. Examples of environmental risks to the 21s: a metal road surface plate, pavement cut for resurfacing. Most car tires sail over these, the 21 is too short to absorb the abrupt impact.

    Do 20s have sufficiently taller sidewalls that they remove the road impact risk of all but the most severe cases.

    Has anyone damaged a wheel on a 20" on their MS, or bubbled a tire from a road obstacle that other cars (or 19's) are not impacted.
     
  17. AnOutsider

    AnOutsider S532 # XS27

    Joined:
    Apr 3, 2009
    Messages:
    11,923
    To toss my hat into the ring, I dropped to 19's and am far happier. I don't have performance tires, but I haven't rashed or bent a wheel yet, and my alignment seems to "stick".

    Also curious of the experiences of the folks that went to 20"
     
  18. simplesolar

    simplesolar Member

    Joined:
    Jun 30, 2013
    Messages:
    250
    Location:
    SoCal
    went down to 20" and it opened up a lot of tire choices for cheap. I am projecting 40k rear and 50k front on my staggered 20"s on michelin pilot supersport.
     
  19. dj905

    dj905 Member

    Joined:
    Jan 16, 2010
    Messages:
    182
    Location:
    GTA, Canada
    Decision made and implemented. I have gone with my option #4 - 19" T-sportline wheels with Michelin Pilot Sport A/S 3 tires. My initial reaction is that they are quieter, somewhat smoother than the 21" Continentals, and my performance seems to be similar when launching from a stop for example.

    If someone is interested in purchasing some 21" wheels (afflicted with curb rash), they have been posted for sale - I'm open to offers!

    Thanks everyone for your input.

    David
     

  20. Keep us updated with any longer term feedback, its always helpful to get perspective from someone that has used both wheel diameters !
     

Share This Page