[s-cars] RETorquing wheels

[Chad Clark]

How true is that statement. If any of you remember, I too had a very scary
experience at the old Stapleton track here in CO about 5 years ago. Had a
local shop put on my track tires, told them torque to 90ft/lbs 20 minutes
into lapping, picked up a shimmy. Progressively getting worse, it got so
bad, I didn't think I was going to make it around to pit. Pulled over on the
track(SCARY!) and couldn't figure it out because of the weight of the
vehicle on the hub/rim. *Barely* limped it into the pits(about 1 thread
holding all five lugs on) The other three wheels had backed out to less than
70ft/lbs per! As Scott mentioned, check torque and re-torque often! If you
ever have a shop put on new tires, check the torque figure yourself ASAP!

Glad you escaped harm free Scott. At least we don't have to worry about this
issue at Steamboat eh? Something about -17* F freezing those suckers on I
suppose:-)

Chad Clark


on 10/14/02 10:26 AM, QSHIPQ at aol.com at QSHIPQ at aol.com wrote:
snip

 Moral:  You can't recheck torque on the wheels enough at a track venue,
race or marque event.  If you *don't* have a torque wrench, get one.  If you
do, use it often.

> Ok, fess up time for me (subject line pun intended read on)....  Instructed
> at the ACCNA even at Gingermann (MI) last weekend with the T44tqw.  Before I
> left on Friday, I rotated tires F/R (235/45 17 HTRZII on17x8.5 Borbet C's,
> Big Reds, 3ml spacer).  Torqued them down to 88ft/lbs, ran thru the usual
> pretrack tech as well.  Saturday, at the track, I passed on a wheel torque
> re-ck...
>
> First run group, I had a marketing director of Michelin tires (a great guy,
> cking out the "track" events for product input) in for a instructor ride.  A
> couple of big guys in a big car, we ran thru the session without much more
> than some agressive braking type shimmy.  At the cool down lap things got
> much more shaky, by the time I headed to pit lane, it felt like a flat tire.
> 50 feet into pit lane, my left front wheel passed me (I was at 3mph at this
> point), right when it fell, I hit the grass.  Hopped out, yup no wheel bolts.
> Mercy.
>
> No damage (other than ego, and enough ribbing to feed an army - Everyone got
> to see the car pitting out), but the 10.9 wheel bolts had left slag in one of
> the wheel hubs, no 14x1.50 taps within 30 miles (more on that), so I was
> done.  Interestingly, I ****found**** ALL 5 wheel bolts (4 perfectly intact,
> 1 buggered) within 20 feet of where the tire fell, so I knew this was a heat
> cycle phenom of some type.
>
> Sunday, I casually mentioned to a former student standing by that I was
> looking for a 14x1.50 tap.  "I've got that"!!!  The three stage type no less.
> Within 10 minutes I was back on the track.  I ran 15minutes of my 30 minute
> run, and came back in to ck the torque.  Easily 20ft/lbs down!  15minutes,
> down another 10.  Yikes!  Finally on the 4th retorque I was good for the rest
> of the day on the left side.
>
> Conclusion?  Not really sure, other than the combination of wheel aluminum,
> spacer aluminum, aluminum hat and steel hub, steel bolts and cold weather
> might have created heat cycles that backed out the bolts.  I was routinely
> pulling the right side wheel off after every run to ck pad wear, and needed
> to retorque the wheels per the above routine.  I had a race buddy that hated
> spacers, I'm gettin there quickly....
>
> Another driver had a wheel leave his car yesterday, stock M3 no spacer, on
> track, he had to walk a lot further to retrieve his (insert more jokes at me
> sharing my torque methods).  Michelins Mr. Green :)/, so those sumitomo
> jokes....
>
> Moral:  You can't recheck torque on the wheels enough at a track venue, race
> or marque event.  If you *don't* have a torque wrench, get one.  If you do,
> use it often.
>
> Humbled by the audi gods and well ribbed
> Scott J
> Newly ascribed member:  3 wheeler club
> Founded:  Mikkola/Hertz 1983 Lombard
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