jw1977

A few months ago I wrote some posts regarding my continual problem with getting my Pzero's balanced. Since then I've been searching the past posts on this forum and came across a few where people said Pirelli's are known for going out of balance and going out of round. This seems to be what's happening to me. I have had these tires balanced 4 times at various shops and they all say there balanced but then sure enough, they feel out of balance. How can this be, that tires can all of sudden go out of balance? It also seems that they flatspot quite easily just overnight. It seems it takes almost an hour of driving before the flatspotting goes away. Do all people with Pirelli's have this problem? Sorry this is so long but the problem has been driving me crazy.

ELUSIVE

This same thing happens to me with my Pirelli's. A set of tire cradles has helped significantly, but not 100%.
I can't wait to replace these things with new tires.

Macster

My direct experience is with Pirellis and Michelins (haven't experiemented with Continentals yet and probably won't) is these tires are sensitive to over-inflation. A few PSI over inflated causes a vague vibration to appear that of course won't be helped by a tire balance.

Be sure to buy a good air pressure gage and check tire pressures cold. Do not over-inflate.

When I ran Pirellis on my Boxster and I ran through a few sets of them (over 100K miles worth of tires), when tire pressure was ok the tires were well-behaved. This has been several years back though and maybe Pirelli tires have dropped in quality. I switched to Michelin tires cause people I know advised me Michelin tires best. The price was not that much more and Michelin tires proved to last a bit longer and exhibit less noise as they wore/aged.

Anyhow, once in a great while a bad tire or two comes down the line.

Are you having the tires load force balanced? This can provide a better balance but if the tire or tires are no good it won't make them good.

Never had a problem with flat-spotting other than in mild temps -- generally in teh spring and fall when daytime temps would climb but night time temps would drop a bit -- is that when I put the car/tires away hot and the car parked outside overnight the tires would cool and take a set. Just a few moments of driving in the next morning would sort this out.

Could be in your case one or more tires have bad belts, that is a bad belt is moving around. The tire will balance but under use the belt will move and the tire will go out of balance, even out of round.

Also, are you running aftermarket wheels? There is a possibility the wheel centering bore is out of round or too large and teh wheel is not accurately registering on the mating diameter of the hub. Even if the tire perfect if the wheel doesn't go on centered the wheel/tire combo will not be smooth.

Sincerely,

Macster.

uzj100

2 sets of P-Zeros, no issues. +1 to Macster's advice on proper inflation.

GSIRM3

I had similar problems on a set of Pirellis and swore I would never own another set. However, my current 2008 C2S came with P Zeros and I have had no issues with them.

alexb76

Pzero (not Pzero Rosso) is a MUCH IMPROVED Pirelli tire. I wish they used better naming not to confuse people.

alexb76

PZero Rosso, or Pzero?

jw1977

Mine is the Pzero Ross and I don't have aftermarket wheels. I run my tires and 33/39 so I don't think that's the issue. I guess I'll try to burn through these tires as fast possible and move on to another brand.

alexb76

People have reported similar issues with Pzero Rosso, just make sure you got the right tire pressure, then burn through them and either change brand or go with the Pzero (not Rosso), which is hugely improved!

Mspeedster

My car came with the P-Zero Rossos. I'm still on my original pair up front and recently got a fresh pair for the rear. I like these tires and have had no issues thus far (knock on wood). These tires seem to get a bum rap here, but at least some of us are satisfied with the P-Zero Rosso. If nothing else, the one thing I like about them (vs. the other N option tires) is the visual pizzaz of the "P-Zero" logo in red, err rosso.

However, since many feel there are better options out there, my next set will surely be one of the newer tire options. E.g. new P-Zero, PS3, or perhaps the cheaper R compounds alternatives like the new Yokohama Advan Neova AD08 or Bridgestone Potenza RE-11.

ADias

Great advice already. I would add - check rims for roundness or bending. Rims are easily distorted by potholes.

jw1977

Thanks for the reply's. I did have a wheel shop check the wheels and they were fine.