I had a track day yesterday. Before I left Chicago, I torqued all the lugs to 95 and then drove to Michigan (about 150 miles). In the morning before I got going at the track, I checked the torque again, torquing to 95 and noticed that the left rear wheel was a little loose on all the lugs...probably at about 75 or 80, but still more than hand tight, so no worries. After three track sessions and lunch (after about an hour of cool down) I checked the torque again, and three of the four were still very solid with almost no change in torque, but the left front wheel was basically finger tight on all but one of the lugs, which was about hand tight. I put the torque wrench on and thought it wasn't working, because the lugs just turned...about two FULL revolutions to get them back to 95. I reached down and was able to UNSCREW one of the lugs BY HAND. I checked again at the end of the day before driving back to Chicago, and everything seemed kosher, but then this morning I was cleaning the wheels off and while drying the wheels bumped one of the lugs and I could UNSCREW IT BY HAND! This was again on the front left wheel and was basically the case for all of the lugs on that wheel to varying degrees. The rest of the wheels were pretty solid with only minimal torquing necessary.

I should point out that these wheels are pretty new, with perhaps 300 miles on them by the time I got to the track. These wheels require a centering ring for the hub, and my guess would be that these centering rings are still getting themselves seated. Also, for the sake of information, I was taking 20 minute runs once an hour. There was a grand total of six runs during the day.

Does anyone have any ideas of what might be going on here? Has anyone else experienced this sort of thing?

Thanks!

 

Having a wheel fall off is a bummer. In the middle of a track session it is not recommended.
Once you install new wheels you must re-torque the nuts after about 25 miles.
Are you using the aftermarket nuts or the orginal MINI ones? Sometimes the length of the bolt is too long so you might try using the other length if you have more than one size bolt. I have both the original and the aftermarket ones and they vary by about 2mm. Once I tighten them I do not have any problems so when I re-tighten them they are all good.

When you are on the track you are really stressing the MINI so that might be the reason they get loose. Keep checking them regularly and re-torque.

 

Are they aluminum? Aluminum wheels have a tendency to loosen the lugs initially, I always re-torque them after a couple hundred miles or a couple days after I put aluminum wheels on.

 

Get a new torque wrench!

also,

Back in the fall of 1955, MG came out with a new model, the MGA. Initially, their knock-offs were all left UNDO, but the factory realized within a few months, that the torque from the vehicle's acceleration from stop was causing the left side rear wheel to UNDO all by itself. The threading was changed, so that the application of torque under acceleration worked to keep the wheel nut tightened. I think that the same principle is working here, although there are four rather than one threaded bolts per wheel. Auto-xing exposes your vehicle to much more torque and other forces than normally encountered on the road. Check your car's lugs frequently, especially when racing. I don't think it is a commonly occuring problem, my thought is that you have a defective torque wrench.

 

If these are aftermarket rims, make sure that the conical seat angle is the same on the wheels as it is on the bolts. Also make sure that the hub surface has no built up rust. This becomes an issue when you change wheel types and the mounting faces end up being different. It's not uncommon for an aluminum wheel to loosen slightly when first installed (heating/cooling cycles and the softer aluminum 'digging into' the steel hub), but to have them back out to finger tight means something is definitely amiss. Painting of rotor or wheel mounting surfaces can cause this, and it's a bad practice to start with.

Also, take it from someone who has seen this happen before: Not always is a single wheel loosening up any fault of the wheel or the car for that matter. It can be caused by 'external influences', namely someone with a lug wrench.

_________________
'03 MCS, Dk Silver, 17" R85s, NAV, DSC (often turned off!), Packs #1 and #3, Rally lights, etc, etc. Fulton, MD. FRS 7-21
Let's Cooperate

 

The wheels are Kosei K-1s, so yes, aluminum alloy (right?). The lugs are the ones that Tire Rack sent to match the wheels and the car. The seat angle looks fine. The hub doesn't have much rust. The lug wrench is damn near brand new, and I can tell that the lugs are *tight* -- I'm not completely incompetent!

 

I just had the exact same issue at Mt.Tremblant. Almost lost a wheel going down the hill after turn 2. Did you solve the issue? I was using the factory lugs, but then swapped to others which were supposidly shipped with the rims. Still moved slightly.

phil.

 

When I read your post I said "I bet he has the Koseis"
This is a trait of all K1s. What happens is that the powder coat in the lug sockets breaks away and the studs loosen. Just clean them up with a soft dremal and get rid of that powder coat in the sockets. After that you won't have any issues.

 

Same thing happened to a set of aftermarket polished wheels on my S during the Dragon.

It turned to be as mentioned above, the clear coat on the wheels was also on the lug bolt holes. The soft clear coat extruded during early use, allowing the lugs to loosen. Checked them every morning for a few days, then no more problems.

Do check new wheels often, until they are seated.

 

thanks for the quick replies!! Mini owners rock!

I'll give that a shot before I mount them again and keep an eye on them. Some other K1 owners were recomending using rounded lugs (vs the straight angled OEM ones) which would really dig them in. The rims are very new, so all the clearcoat is still on them.

Thanks!

phil.

 

Onasled beat me to it.
My money was, or is, on powder coating. Sand it off with a dremel tool.

 

I had the same thing happen 2 weeks ago at a track day. They were Rota's with Toyo RA1's mounted. Torqued at home, 30 miles later at the track and after the first session. I almost lost the left front wheel, the lugs were out about a 1/4in

I will clean the seats before using them again. Thanks for the great post

 

Have not seen this with the Rotas. Make sure that is actually the problem.

 

I had two Rota Subzeros strip and powercoated and on those two I have an issue with the lug bolts becoming loose. I need to clean up the wheel with a rotary tool.

 

I used the same lug nuts that I use for my other set of wheels, Centerline RPM's and have never had them loosen up during track use. The only other difference was a newly installed Wilwood BBK. Do the Rota's use a different lug nut? Could the aluminum brake hat be part of the problem? I haven't heard of any problems with the BBK's.

I looked at the lug nut seats last night and all of them showed flaking of the black finish in the tapered seats. It still sounds like that might be the reason they got loose.

 

The Rota's do loosen up. I need to finish removing all the paint from under the lugs. After the first autox run on R-compounds I re torque them and all is good.

 

Same deal with a buddy's K1s.
Jim

 

I did a track day yesterday at Thunder hill in Willows CA.
I have a pretty new set of Team Dynamics Pro race 1 wheels with
R-Comps on them for the track. After my first run they were
out of spec on torque so I cranked them back to 95 ft/lbs.
Then I figured all was well... I pushed it pretty hard for the next few
sessions and got the brakes really hot and "melted" the finish
of the wheels under the lug bolts - they were only slightly more than
finger tight after that. Another session and I may have lost
a wheel!! I'm taking a dremel to them before I use them again
Thanks for the advice onasled and others.
-G

 

I am an instructor with the Golden Gate Chapter of BMWCCA and just finished a track day at Infineon with my 2006 JCW-S (with the new and improved bigger 14mm lug bolts). Torqued wheels before leaving home and again at the track. Front left wheel almost fell off at the end of my third session!!!! All 4 lugs were barely even in there holes and could easily be remove with very light finger pressure. This is very strange and is a serious problem. If I hadn't felt a small vibration and pulled off track I would have lost a wheel big time. These are Konig wheels (which I might have blamed for the problem except the same thing happened TO THE SAME WHEEL with my factory S-lites and stock run flats. If the issue is a finish problem why is it only one wheel???? All others were quite tight.

Has anyone reviewed this with the dealer or Mini and gotten any satisfactory response. I may be pushing the car hard but theat's why I bought a JCW. It's hard to believe that I will have to check torgue after every run.

Any thoughts???

 

Few thoughts on this thread (and yes I was jealous I didn't know about today being a track day until I checked the date on the OP)

1. One of my last checks before putting on my helemet is before EVERY run on a track I check my torques. (safe than sorry although I've never had more than an 1/8 adjustment on any lug between them, with OEM wheels that often do months of street driving without coming backa t all)

2. Front left wheel will see the most stresses. (Transmission and occupant is on that side of the car and assume the engine basically centered and thats a 500 lbs bias between the two fronts on a car that is 2600 or so lbs.

 

Two reasons;
1. Check lugs after every session.
2. LF is the primary drive wheel. This one is going to "throw the nuts" by way of rotation. For this very reason most serious race cars have LH thread on the left side of the car.

 

i'm missing what exactly needs to be sanded...
you're talking about the inside of the wheel? under the bolt hole of the wheel? the back part of the bolt hole?
is this it?

Or is it the lugnut seats?

a pic would help, i'm confused as mine have never loosened up and i drive it pretty damn hard...(Team Dynamics 1 with 14mm studs)

 

You sir are 100% correct.

NEVER EVER put your car on the track without first checking the lug toque & air pressure. Every session!