Skip to main content

Add new comment

John Goreham    June 24, 2014 - 1:39PM

In reply to by RR (not verified)

Congrats on owning an M. I saw the new M4 this week and it looked awesome. Actually, on an M car I can understand the use of run-flats. They are heavier than regular tires, which is a negative on a car that puts so much focus on weight savings, but I can understand it. On a passenger car I don't think they make good sense. I understand you got a "blow-out." To me a blow out is when a tire depressurizes instantly due to major damage (from failure or from striking something) and the tire comes apart partially or completely. A puncture or a "flat tire" is when the tire loses pressure due to a hole or a foreign object embedded in it. Blow outs simply do not happen with modern radial, low profile tires that are properly maintained. They are incredibly rare. Punctures do occur and the mandated TPMS system will alert a driver of the drop in pressure. One can always choose to then slowly exit the highway via the breakdown lane. It may destroy the regular tire, but run flats driven flat are also destroyed. The videos I have seen do not convince me of a needed safety advantage. Road debris can also tear sidewalls on run-flats, so they are not a guarantee that if something large is struck they won't also be un-drivable.

The content of this field is kept private and will not be shown publicly.
  • Allowed HTML tags: <em> <strong> <cite> <blockquote cite> <ul> <ol'> <code> <li> <i>
  • No HTML tags allowed.
  • Lines and paragraphs break automatically.
This question is for testing whether you are a human visitor and to prevent automated spam submissions.