run flat tire or an inflation kit that mixes air and sealant.
The secret of run flat tire is basically having stronger side walls so that flat tire will not deflate that quickly. Your top speed is limited as well as touring range. However the idea is, you should have enough mileage to drive to the nearby mechanic to have the tire replaced (with another expensive run flat tire). If you are in the Australia outback where the next service station is 200km away, well then bad luck (and wished you have joined NRMA)! Again, the assumption is, as long as you are around the metro area, you should have no problem replacing a flat tire...
But it is not true!!
I went to MBF Bible study last night, and parked my car on High Street just outside the University. When I exit the car, I could hear the sound of "leaking air". By the time I have realised what was going on, the tire on the front passenger side was completely deflated. Fortunately our old Nissan Pulsar N14 comes with a full-size spare, and it took me around 15 minutes to do the swap so I do not have to do it in the dark later. Still on time for the Bible study!
Then we went to Maroubra this morning to have the flat tire replaced. Disappointingly, neither Goodyear, Beaurepaire nor Kmart Auto on Maroubra Road could do it for me today! It was like everyone was having flat tire party this week and they all told me that they had so many to replace. The earliest that can be done is Monday.
No problem. My car is still riding on its full-size spare. And finger-crossed -- that I won't have another flat tire this weekend.
However, imagine I am driving the latest BMW E90 3 Series (oh I wish) with only run flat tires. Then the monitoring system notified me that I have a flat tire. No worries mate! I live in Sydney and there are plenty of repair shops that can replace my run flat tire. Except they are all busy! None of them can replace my gradually deflating tire and the earliest can be done is next Monday -- which means my beloved Beemer will be sitting in the garage for the whole weekend!
Here is another analogy for the geeks. Full size repair is like having a RAID 5 for your computer. There is always one hot spare, and you are safe as long as you don't have two failed
drives tires. Run flat tire or the inflation kit is like having a copy of "SpinRite" with your PC. When the disk drive started degrading, you just pop those disk maintenance utility in, and hope your data can be recovered. You still need a replacement drive, and the data recovery is never guaranteed.
Moral of the story? You just cannot assume that run flat tire is safe in urban area. Then again if you are driving a Beemer, you won't go to Beaurepaire or Kmart Auto to have your tires repaired.
Oh, also the announcement that I had a flat tire on Friday.