Tire Wear Analysis Request

Discussion in 'Track Days & HPDE's' started by RonsMinnie, Jul 6, 2010.

  1. RonsMinnie

    RonsMinnie New Member
    Lifetime Supporter

    Jul 28, 2009
    449
    5
    0
    Sugar Land, TX
    Ratings:
    +5 / 0 / -0
    This a base Cooper Clubman with standard diff. The Sway bar is a NM 22mm set in center position. I just do not remember getting a lot of wheel spin, This was almost completely a third gear course and with a base Cooper this makes it harder to spin the tires. Perhaps Vader (my instructor) can comment. I will check the toe, but I do not see any feathering in the tire wear.
     
  2. Vader

    Vader New Member

    Oct 7, 2009
    45
    2
    0
    Ratings:
    +2 / 0 / -0
    I feel confident that we can rule out wheel spin.
     
  3. Alan

    Alan Active Member

    May 6, 2009
    353
    98
    28
    retired
    New Braunfels, Texas
    Ratings:
    +98 / 0 / -0
    I would take some camber out of the rear, and set the bar to full stiff.

    My fronts tend to wear on the inside and the rears on the outside. So rotating tires balances things out. The front insides wear because of braking. Rotate front to back and as the tread disappears you can rotate across the car as well.

    -2.3 Front 0 Toe
    -1.3 Rear 0 Toe

    p.s. I was in the BRG/B parked next to Tony. Sorry we didn't get time to chat during the event.

    HOWEVER - since this was your first DE. Keep the car set so it feels comfortable to you. As you gain more experience you can loosen the car up.

    I'll see you at MSR on the 17th?
     
  4. RonsMinnie

    RonsMinnie New Member
    Lifetime Supporter

    Jul 28, 2009
    449
    5
    0
    Sugar Land, TX
    Ratings:
    +5 / 0 / -0
    What a gentleman!

    He did that without adding any of those laughing "smile" icons.
    That had to be very tempting -- thanks
     
  5. mini_racer

    mini_racer Well-Known Member

    May 4, 2009
    1,046
    57
    48
    Engr Manager
    Austin, TX
    Ratings:
    +57 / 0 / -0
    #25 mini_racer, Jul 7, 2010
    Last edited: Jul 8, 2010
    Alan, do you run that -2.3 on the street any significant amount? That seems like a bunch of camber for the street. I am just running -2.0 on street and track, but I bet -2.3 would feel better on the track.
     
  6. Alan

    Alan Active Member

    May 6, 2009
    353
    98
    28
    retired
    New Braunfels, Texas
    Ratings:
    +98 / 0 / -0
    Yes, I do run those settings on the street. I run my street tires at least 5 psi over the recommended pressure so I don't wear out just the inside edges. Over inflation forces the wear across the middle of the tires as well. Even so I wear out the street tires across the inside half.

    My street tires are also my rain tires and back up tires. So they do see track time as well. I ran them the last two sessions at H2R cause I corded the Advans Sunday morning.
     
  7. Mrsideways

    Mrsideways New Member

    Apr 12, 2010
    85
    5
    0
    Ratings:
    +5 / 0 / -1
    I didn't read that it's a cooper. I would highly doubt he's spinning them hard enough especially with an instructor in the car. You've gotta drive it pretty on edge to roast a tire in that car like that. Don't get me wrong it can be done. My 130whp 90ft/lbs of torque Honda Civic in Showroom Stock Trim could roast an inside tire (hoosier at that) if you drove it like a qualifying lap. But I have my doubts it was being driven like that and the rest of the wear doesn't show that kinda driving. Tire pressure might have been high but that won't cause the wear your seeing. It's pretty well gotta be tow out in the front by process of elimination. Maybe worn control arm bushings causing the tow to move in varying conditions.
     
  8. maacodale

    maacodale Club Coordinator

    May 7, 2009
    546
    255
    63
    Maaco Collision Repair & Auto Painting Center owne
    Poquoson, VA
    Ratings:
    +265 / 0 / -0
    Just to throw a few ideas out there. If it were high pressures it should wear more in the center of the tires. If it were a lot of toe out, you'd see feathering of the treads. I don't see either. I personally see a negative camber issue. That is the only cause, in my opinion, that would wear rapidly on the inside and a lack of wear on the outer edge. I'd get it to another (good) alignment shop. BTW, do ya have camber plates on the car? I'm still blaming camber.
     
  9. Mrsideways

    Mrsideways New Member

    Apr 12, 2010
    85
    5
    0
    Ratings:
    +5 / 0 / -1
    Hmm, I've run street/track cars in the past with VERY large amounts of camber. I had a M3 I ran -3.5 in the front and -3 in the rear. I drove it for about 80k miles with that camber. Running a 280 treadware tire I would get about 15,000 miles till the VERY inside edge of the tire was worn heavily, I'd pull the tire and flip it on the wheel and get another 10k before the tire was done. The other thing is the camber would only wear the very inside edge, no more then 1 inch in from the edge got heavy wear.
    Now I just had this happen last week. I put a steering rack on a customers (volvo) a little under a year ago. I told her to get it aligned, She put new tires on it but never went to get an alignment. She drove it 8000 miles with a fare amount of toe out in the front. 560 treadware tires looked identical to the tires in the picture after only 8k with I believe I measured it to be 1/4 inch total toe out and stock camber which is -.5 or so.
    Camber won't kill tires, Toe will. Camber + toe however will really kill a tire. I'm betting that if the things aligns at Zero Toe then something is moving and causing a toe issue. Control arm bushings come to mind and are a known failure.
     
  10. maacodale

    maacodale Club Coordinator

    May 7, 2009
    546
    255
    63
    Maaco Collision Repair & Auto Painting Center owne
    Poquoson, VA
    Ratings:
    +265 / 0 / -0
    Negative camber on the street isn't terrible I agree. My old autocross Camaro routinely would run -3.5 camber and wasn't bad. But track time and negative camber can wear insides. I still say excessive toe will give you a feathering of the treads that I didn't see in those pics.

    And I totally agree, if alignment specs look good, I'd start searching for movement. I also agree, that the control are bushings are likely a culprit.
     
  11. RonsMinnie

    RonsMinnie New Member
    Lifetime Supporter

    Jul 28, 2009
    449
    5
    0
    Sugar Land, TX
    Ratings:
    +5 / 0 / -0
    More Details:

    The MINI has Vorshlag camber plates. The control are bushing are PSRS's and have been checked for tightness. This setup has about 3,600 miles thus far.

    The steering is tight, no vibration, no noise.

    The alignment was done by a performance shop that was very meticulous in there approach to the job (does not mean its right - but they certainly worked slowly and carefully & does not mean something has not changed since the alignment).

    Again Thanks to all for their help.
     
  12. RonsMinnie

    RonsMinnie New Member
    Lifetime Supporter

    Jul 28, 2009
    449
    5
    0
    Sugar Land, TX
    Ratings:
    +5 / 0 / -0
    Toe was the problem

    Here is an update on my tire wear problem.

    Took the MINI in to an alignment shop flipped the front tires on the rim and rotated the front and had the alignment checked.

    This was at a different shop and they found all previous settings good except front Toe which was a -1.38.

    Corrected to +.22 (this setting is very touchy-they would just breathe on it an it would change).

    Wear after HPDE at MSR Houston in pic below - practically no wear on inside with new Toe setting.

    [​IMG]

    Thanks to all -- Especially Khuevo!
     
  13. mini_racer

    mini_racer Well-Known Member

    May 4, 2009
    1,046
    57
    48
    Engr Manager
    Austin, TX
    Ratings:
    +57 / 0 / -0
    Great to see that you have this issue resolved, congrats.
     

Share This Page