Deformed tyres - who's had them?

[LactoseJoe]

Just got my latest pair of Nankang NS2R tyres and they've turned up slightly out-of-round (egg shaped) and are vibrating at >70mph. It's visible when spinning the wheel with the car in the air - wheels are fine. I usually run Accelera 651S - another budget track tyre - but the lack of sidewall stiffness led me to try something new. In the past, I've had three of the Acceleras turn up egg shaped but the supplier has always been good and just replaced them on demand. This time, I've covered a mere 80 miles - just one track day, plus commuting - and have noticed the vibration. I have reached out to the supplier and they seem to be refusing a return, or more accurately have suggested "bedding-in" the tyres for 200 miles first. On the phone they said they won't guarantee tyres that have been used on a track.

Last night, I began searching for answers, and as it turns out, this seems to be quite commonplace across many manufacturers, not just the cheap brands. I found quite a lengthy thread on bobistheoilguy filled with people complaining about out-of-roundness with a whole spectrum of tyre brands. Some say they get the tyre road-force adjusted and some said there are skimming services available, all of this was news to me.

I do believe some of the sensitivity might be with the car's setup, being pretty tight with all new stiffer bushes and a couple of rose-jointed arms in there. But this can't be right, surely? How can you sell track-focused tyres that vibrate at public road speeds.

Well, the car doesn't do much driving right now and basically just drives to and from the track, and then to the workshop. I won't see the next 100 miles completed for a couple of weeks and I get the feeling the supplier will come up with something to avoid replacement. I've also queried this with Nankang, so let's see if they have any input. But my question is, have any of you experienced this and has bedding-in actually fixed anything?

[Griffith4ever]

Had a 996 C4s with a deformed tread on one of the fronts (expensive tyres). HAd the car looked at by the dealer with suspected front diff howl to no avail. Went to an indy, no luck. Went to another indy, took him out for a drive, "that's your tyres mate". Changed the fronts, noise gone.

[RizzoTheRat]

Is the bead definitely seated correctly? Not seen it on a car but had it on a bike where it hadn't fitted in properly. I deflated the tyre and gave it a bit of massage and it dropped in properly.

[Bobupndown]

"On the phone they said they won't guarantee tyres that have been used on a track."

Don't tell them?

[LactoseJoe]

It is very strange, especially simultaneously on both fronts. I've found hit and miss information out there. What's especially strange is that I've been through so many tyres in the past but in the last few years had at least two tyres plus the current two with this problem, always at the front. Common denominators are the wheels, car and the installation shop. The car will be shipped out of the country in a few months so If I can't get to the bottom of it here, I'll do it in my new home. I'll give it another check this weekend and go for a sprint up the motorway. Both tyres show obvious movement when spun on the car, about a few mms. The most important thing is re-confirming the wheels are fine - they're too expensive to replace in Europe.

Maybe a burnout will sort them out.

[Griffith4ever]

Bobupndown said:

"On the phone they said they won't guarantee tyres that have been used on a track."

Don't tell them?

Even if they don't, that can't mean they can circumnavigate consumer law where the goods should have been free from defect at point of sale.

[LactoseJoe]

Bobupndown said:

"On the phone they said they won't guarantee tyres that have been used on a track."

Don't tell them?

Ah yes, about that. They asked for pictures of the tyres mounted on the car, and the pictures I sent had melted rubber on the surface. Like I said, not many miles and it was a track day.