Two of my last runflats had very light bumps in their sidewalls - very light rises in the rubber discernable only by touch. Rode them to natural death .

Now i have a slow leak i don't know where. A tire garage, asked to find the leak, drew a white box around a barely discernable rise. Tells me I have to buy a new tire. Tells me they're giving me a deal on a $312 runflat. tells me there's no use finding a leak, the tires condemned.

My favorite online source specials the same tire at $157ea. My mechanicly knowledgeable friend says there's very little chance of that tire expiring before any other. That belts may have been displaced, but that's all.

i'm not expecting an ok from goodyear, but am i really to be alarmed about these things?

 

For ultimate safety, you should replace any tire which has an abnormality.

That said, I hit a ***** of a pothole driving my car home from VA an got a 'rise' in the sidewall. It got me the rest of the 800 miles home, and drives around just fine. It makes me a bit nervous to drive it hard in the twisties, but I haven't given up on it yet. Given their design, the runflats should be able to gracefully suffer a failure. Heck, they're DESIGNED to be driven for 50 miles with NO AIR. The sidewalls have to be significantly reinforced, so I can't foresee a catastrophic failure that would endanger me.

As for your slow leak, try 'painting' the bead with a soap/water solution. Ideally you'd remove the rim and put it in a container of water (the bathtub, if you're single ) and spin it around until the leak makes itself known.

 

I have Goodyear runflats on my MCS and two of them are welted, One just slightly and the other was quite big. Mine did not leak, so I alot of caution was able to put another 7 thousand miles on em. I'll be springing for some non RF's this time, soo much cheaper. Good luck

 

I've seen a few runflats with their sidewalls "blown out". According to my service writer, the sidewall can compress slightly when it hits a pothole for example. (Lots of those around LA now.)
This pinching can allow air to slip between the inner and outer walls of the sidewall thus creating an air blister. (Ever had a blood blister? Same thing) If the pressure builds up, the outer wall will blow thus ripping the sidewall. Even though the runflats have very strong sidewalls, you are losing a lot of structural rigidity when the inner and outer walls are separated. If you see a bubble forming, you may wish to replace the tire.

The idea of runflats was to offer protection from damage to the tread, not the sidewall. Since most flat tires are caused by punctures to the tread, the extremely hard side wall of runflats maintain the overall roundness allowing the tire to continue to rotate. But a blown out sidewall isn't the same thing.

My dealer has taken to inflating the 17" runflats on MCS to the full 38 pounds. They claim that the additional inflation reduces the compression factor of the tire helping to prevent blisters from forming as well as protecting the rim of the alloy wheel from the sharp edge of potholes. I don't know if this is really true or not, but that's what they say.

 

Thanks for your resposes.

I am dying to replace my all-season runflats with the Pzero Assymetricos I love... But now is not the time. One runflat just does not run that much anymore, and four performance tires still do.

As far as safety - I am concerned. I will eye the suspect sidewall daily - easy to remember as it is still leaking air. Maybe soon order it's replacement.