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Discussion Starter · #1 ·
My question is how to avoid tire rotation on the rim during hard braking.

I mark off the valve stem on my tires so I can see if the tires are rotating on the rims during heavy braking. Most of the time I see between 5 and 30 degrees of rotation. As I drive the car to/from the track, most of the time the small change in balance is not something I can feel. But this last time I can definitely feel the imbalance and I will get the wheels all properly balanced. Now to my question, I read on Rennlist an old posting where people stated that this rotation can be eliminated by using hair spray for the tire bead - the idea being that soap never really dries but hair spray initially acts as a lubricant but then dries like glue. Is this idea of using hair spray valid? I feel like such a fool even asking as I have unlimited tire balancing but I would like to avoid the issue as I had a long drive home last time and I could feel the pulsing in the steering. Thanks in advance.

And as a follow-up question, in trying to research this I found some postings that say you should balance the rim alone first and then balance again with the tires. The idea is that the weight placement is more exact. Any comments here?

Thanks in advance.

PS Loving the Toyo A052
PPS Thoroughly enjoying Big Willow and shout out to the PCA SDR guys for their two day event this past weekend.
 

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The hairspray trick has been long used to get bicycle handgrips on (when wet) and to prevent rotation (when dry). It’s effective in that application. That said, I’d be surprised if hairspray has the sort of holding power required to keep a tire from rotating on the wheels of a 3000+ lb. vehicle when decelerating from triple digit speeds (in some cases).

I’ve not heard of doing the “double-balance” that you describe, but it makes logical sense.

That said, some manufacturers make rims with a knurled tire bead. This must be the most effective, albeit pricey, solution.



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Titan 7 TS-5's with knurled tire beads seat. I have a set and love the look. Forged and very light weight. Finger spokes allow you to wash your calipers and barrel very easily.
 
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Discussion Starter · #4 ·
Thanks for the inputs. I've been poking around and knurled beads is the way to properly address the issue but too pricey for me. Another suggestion I have read is to use Permatex hi-tack. I think for now I am just going to have the wheels rebalanced - my next drive is not a long one.
 

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I tend to do balancing and alignment every 6 months or every oil change as part of maintenance but even then, a DE/track day will usually ruin it as the tyres pick up a lot of rubber on the circuit and the tyre pressure fluctuations require air pressure reduction/top ups so the whole car tends to need a good balancing and alignment after a session. make sure to run off the excess rubber first though! Usually takes a couple of days at least....
 

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I have never heard of tires rotating on the rims. Is this a common thing??
It is on dirt track racing. We would run very low pressures, and it required bead-locks or sheet metal screws through the bead.
Same problem on off road motorcycles.

But I guess on extreme high traction braking, there's enough force at play on even higher air pressures?

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Discussion Starter · #8 ·
I tend to do balancing and alignment every 6 months or every oil change as part of maintenance but even then, a DE/track day will usually ruin it as the tyres pick up a lot of rubber on the circuit and the tyre pressure fluctuations require air pressure reduction/top ups so the whole car tends to need a good balancing and alignment after a session. make sure to run off the excess rubber first though! Usually takes a couple of days at least....
Thanks. I am counting on the drive to/from the track to help with removing the excess rubber. I do peel off what I can when I get them off. I have lifetime free rebalancing so I will just rebalance after every event.
 

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Discussion Starter · #9 ·
It is on dirt track racing. We would run very low pressures, and it required bead-locks or sheet metal screws through the bead.
Same problem on off road motorcycles.

But I guess on extreme high traction braking, there's enough force at play on even higher air pressures?

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I find myself occasionally tripping ABS when I have to lose a lot of speed for the next turn. The Toyo's are very sticky tires. The track is usually quite hot so the tires are really gripping. I think the hard braking is sufficient.
 

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I can only imagine how much the sticky Toyo's pick up.
Even on the PS4S, it takes me at least 100-200 miles to get rid of the excess rubber - yes I'm not that great at racing lines.... ;)

Thanks. I am counting on the drive to/from the track to help with removing the excess rubber. I do peel off what I can when I get them off. I have lifetime free rebalancing so I will just rebalance after every event.
 

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I've heard of some people just balancing the rims without any tires for this reason.
 

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Stickier tires will spin much less (if at all) on the rim. I have been autocrossing for 30+ years and have never had an issue with that. Make sure you buy a good set of grippy replacement tires. Your Porsche deserves it. :)
 

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Discussion Starter · #13 ·
Stickier tires will spin much less (if at all) on the rim. I have been autocrossing for 30+ years and have never had an issue with that. Make sure you buy a good set of grippy replacement tires. Your Porsche deserves it. :)
Thanks for the response but I have to say I don't understand your logic here. Ignoring the stickiness for a moment, and the Toyo's are 200, the issue with rotation has to do with the torque being applied to the area of the mating surfaces of the tire; to the rim and to the road patch. Even if we ignore that the friction coefficient of the sandpaper-like road is significantly more than the painted & smooth bead, more importantly, the road patch area is at least an order of magnitude greater, than the rim bead area. So it seems to me that all that is needed is sufficient torque to overcome the friction of the rim bead area. Given the significant torque going on track, I was at Big Willow coming into T1 doing 130+ and had to slow to 70+ so the tires are really working hard. I think where you were going is the suggestion of using some kind of glue on the bead to more even out the holding capability of the bead versus the road. Others have suggested this as well and that would definitely raise the torque minimum.

For my next set of tires, I am going to try Ledbette's suggestion of balancing the rim, and then the tire rotation will hopefully have less of an impact.
 

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I just did a track day, and marked tires like you - same results - tires are slipping on the rims. Rears rotated close to 3", Fronts about 1" in 5 sessions. C-GTS, 19" wheels with knurled seats, Bridgestone RE71R (200TW) tires. Wheels and tires were new - first mount. No significant vibration yet.

I don't have all the answers yet, but some ideas from online: 1) have the tech clean the bead seats with acetone before mounting. 2) bring them a spray bottle of Isopropyl (rubbing) Alcohol, and have them use that as a mounting lubricant. This should provide enough slip during mounting, and then fully evaporate. The typical mounting paste used by tire shops probably leaves a residue that's too slippery for track use.

Adhesives: It may work, but I'm leery of this method, mainly for the mess and the cleanup that will be needed for the next mounting. I saw one post suggested using 3M Contact Adhesive. Permatex and hairspray also possible.

Others have suggested roughing up, sanding or bead blasting the bead surface to get better grip between the wheel and tire bead.

Of course, check to see if any wheel weights missing, and clean tire rubber from the barrels.

Or, if you have free balancing, that's easy ;-)
 

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Thanks for the response but I have to say I don't understand your logic here. Ignoring the stickiness for a moment, and the Toyo's are 200, the issue with rotation has to do with the torque being applied to the area of the mating surfaces of the tire; to the rim and to the road patch. Even if we ignore that the friction coefficient of the sandpaper-like road is significantly more than the painted & smooth bead, more importantly, the road patch area is at least an order of magnitude greater, than the rim bead area. So it seems to me that all that is needed is sufficient torque to overcome the friction of the rim bead area. Given the significant torque going on track, I was at Big Willow coming into T1 doing 130+ and had to slow to 70+ so the tires are really working hard. I think where you were going is the suggestion of using some kind of glue on the bead to more even out the holding capability of the bead versus the road. Others have suggested this as well and that would definitely raise the torque minimum.

For my next set of tires, I am going to try Ledbette's suggestion of balancing the rim, and then the tire rotation will hopefully have less of an impact.
My bad. I didn't realize you were racing the car. I thought this was occuring from normal street driving. (my bad for skimming the thread). Crazy that you will have to resort to glue...that would make me nervous. Hopefully the glue will be easy to clean off the rim when it's time to replace the tires. (reminds me of using tubeless mountain bike tires with sealant inside. It's a mess to clean off the rims when it's time to change tires)

Good luck though. Keep us updated on what you find out! :)
 

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I agree glue made me nervous as well which is why I am going with the Ledbetter solution of just balancing the parts that won't change.
You probably know this already, but make sure to use some aluminum tape to hold those weights on. I've forgotten a few times, and after a weekend, ended up with half the weights I started with and the ones I still had were all over the place.
 

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Discussion Starter · #18 ·
You probably know this already, but make sure to use some aluminum tape to hold those weights on. I've forgotten a few times, and after a weekend, ended up with half the weights I started with and the ones I still had were all over the place.
Thanks. A friend pointed this out to me not that long ago. I carry an extra roll of the tape just in case.
 
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