Tires slipping on track wheels

[JScheier]

This is totally normal. Slippage happens on every type of rim/tire combo on the track. For this and all the reasons discussed re pickup, balancing race tires is totally useless.

Not to mention that loose wheel weights are pretty dangerous on track (tossed or run-over).

 

[cosm3os]

That, too. Make sure if you are using them you throw some alum tape over them.

 

[cloud9]

That, too. Make sure if you are using them you throw some alum tape over them.

I had the track side tire guy at the NASA Road America event flip my Hooisers on the rim. He balanced them and put alum tape over the weights so I assume he does that on all the race tires at the events he works.

 

[JScheier]

I had the track side tire guy at the NASA Road America event flip my Hooisers on the rim. He balanced them and put alum tape over the weights so I assume he does that on all the race tires at the events he works.

What I've found is that if I bring a set of wheels / tires up that have weights on them to a track-side vendor, I get them back balanced. If I bring a set of wheels / tires that do not have weights on them I either a) don't get weights back or b) get asked if I want them balanced.

I have a new 'sponsor' that is a tire store. They mount and balance my tires for free in exchange for my car being displayed at their shop on some weekends. Most of the time I pull the weights off before mounting them on the car. If they have gone to the effort to add tape, then I usually leave them as 99.9% of the time I'm running behind and don't have time to mess with it.

 

[blacksheep-1]

First off whenever you get tires mounted you should turn over a set of wheels with the weights off and the wheel clean, Conti calls it their "de weight and deflate " policy. By cleaning the old weights off and cleaning the wheel with lacquer thinner you are insuring that the new weights will attach, then you metal tape over them to keep them there. As far as tire rotation, I used to mark the location of the valve stem, then watch as the tire rotated on the wheel, it used to drive me crazy, then I realized that it was mostly the wheel that was being balanced an not the tire, so I just quit marking them because it was making me crazy. The only time we've had a vibration issue is when we've thrown a wheel weight.
FWIW when OEM wheels are made their centers are often off, the tire is then mated to the wheel and the valve stem location rotated to the location that makes the whole assembly the most "round". Once you change tires, and they have no valve stem location marked on the tire (ultra hi performance tires will) or you change to an after market wheel, you give up this minute amount of detail that keeps the wheel/tire assembly true. In 99.9% of cases, it's not enough to matter but if ALL the discrepancies line up then it can create a vibration issue.

 

[lbp]

The Nitto's are also slipping on the Enkei's. Here's a pic after 1 session. Valve was originally aligned with silver line:



Other side:

I've heard that bead blasting the rim contact area can cure this.
- Might need to re-inflate each day?

 

[blacksheep-1]

The only thing I,ve seen that cures this completely is bead locks..srsly I would quit worrying about it unless you have a vibration.

 

[steveespo]

OK had no tire slip at all through 5 1/2 hours of track time at WGI yesterday and Mondday, which was about the only good thing I'd say about the Toyo R888. Black Boss and I spoke with the lead mechanic on a Canadian Viper ACR World Challenge team who gave us the following info;
Don't sandblast the bead surface, if anything use walnut shell media, even that makes it difficult for tire tech to get the tires to bead seat.
Clean the bead area of the tire with brake cleaner on paper towels, he mentioned a specific brand but I don't remember it , clean the rim with it too using a red scotch brite pad.
Ask the tire tech to use isopropyl alcohol as a lubricant instead of tire soap. He said it works and leaves no residue behind.
He also balances all of his tire sets but said many teams don't because of slippage. Michelin slicks are the worst he experience, but with his methods he gets them to seat and stay in place.

It was very good talking with them, they had 3 Vipers which were very nice and very fast on track.
Steve

 

[blacksheep-1]

You guys are going to make yourselves go crazy over this....lol

 

[ArizonaBOSS]

You guys are going to make yourselves go crazy over this....lol

Not I!!

 

[JScheier]

Not I!!

Nor I.

 

[steveespo]

I'm not crazy over it, got it covered now. If they slip they slip if not they don't.

 

[wwilde001]

No slippage here on my BBS's in 5-1/2 hours of driving at VIR this past weekend.

 

[Black Boss]

You guys are going to make yourselves go crazy over this....lol

Not me either -- Just want to understand the physics!

Like Steve, I had very little (on 1 wheel) to no slippage (3 wheels) at the Glen on the same (re-balanced) wheels and tires that slipped like crazy originally. I think this is the best fix explanation:

OK had no tire slip at all through 5 1/2 hours of track time at WGI yesterday and Mondday, which was about the only good thing I'd say about the Toyo R888. Black Boss and I spoke with the lead mechanic on a Canadian Viper ACR World Challenge team who gave us the following info;
Don't sandblast the bead surface, if anything use walnut shell media, even that makes it difficult for tire tech to get the tires to bead seat.
Clean the bead area of the tire with brake cleaner on paper towels, he mentioned a specific brand but I don't remember it , clean the rim with it too using a red scotch brite pad.
Ask the tire tech to use isopropyl alcohol as a lubricant instead of tire soap. He said it works and leaves no residue behind.
He also balances all of his tire sets but said many teams don't because of slippage. Michelin slicks are the worst he experience, but with his methods he gets them to seat and stay in place.

It was very good talking with them, they had 3 Vipers which were very nice and very fast on track.
Steve

I'm also considering CCW wheels for the Slicks in wider widths. Talked to John @ CCW today and he said that tire tolerances are the major culprit in slippage, and that knurling or other methods can lead to pressure loss.

He also recommended 10.5" up front and 11" rear compared to the 10/11" set-up I was considering.

 

[blacksheep-1]

Not me either -- Just want to understand the physics!

Like Steve, I had very little (on 1 wheel) to no slippage (3 wheels) at the Glen on the same (re-balanced) wheels and tires that slipped like crazy originally. I think this is the best fix explanation:

I'm also considering CCW wheels for the Slicks in wider widths. Talked to John @ CCW today and he said that tire tolerances are the major culprit in slippage, and that knurling or other methods can lead to pressure loss.

He also recommended 10.5" up front and 11" rear compared to the 10/11" set-up I was considering.

I has that same conversation with john awhile back, CCWs are much harder to mount, (the conti guys don't like them but they got used to them) for road racing I can't recommend any other wheel, the CCWs are very robust, we had a car hit a wall, the axle was shoved over, but the wheel remained intact. They are pretty much "fire and forget" units, but like everything else, they need to be inspected regularly.

 

[VoodooBoss]

I'm going to mark mine for a track day at Sonoma this weekend so I can join this madness.

 

[skwerl]

A trick popular with drag racers is to use a little Permatex High Tack gasket sealant on the bead.

 

[Voltwings]

Assuming our tires are slipping (i'm very much a novice, so likely not a problem i will have any time soon) how often, if even, should you get them re-mounted to make up for it? Thanks.

 

[patrickshelby]

Would it make sense to balance the bare wheels, new and clean, and then mount the tires (indexing to the stem when possible) without further balancing the assembly, ever...?

 

[Roadhouse]

I think the consensus is that it's not a huge deal if the tire slips on the wheel...