Have Runflat Tires Finally Come of Age?

Ever since BMW made the switch to run flats we ‘ve been waiting patiently for the technology to mature to the point of being transparent. Transparent meaning that there ‘s no trade-off in feel, performance and comfort as compared to the tires we ‘re all used to. With the launch of the 3rd generation of run flats, tire makers – specifically Bridgestone – may have finally done it. Our friends at Tirerack recently tested the Bridgestone ‘s third generation run flat and came away very impressed with the results and the tech behind it all. Here ‘s an excerpt:

Bridgestone ‘s new third generation (3G) run-flat features a sidewall design that helps minimize the run-flat tire ‘s negative influence on ride comfort. While still thicker than a conventional tire, the signature features of the 3G run-flat sidewall are a unique exterior cooling fin design and special rubber compound, both designed to reduce the heat buildup that occurs while driving on a tire that is no longer inflated. Reduced heat buildup during run-flat operation allows for the thinner sidewall design, ultimately improving ride comfort.

Out on the road our team found the ride quality of the Potenza RE960AS Pole Position RFT run-flat tire to be very similar to the conventional Potenza RE960AS Pole Position, with a small advantage to the conventional version. The older-generation run-flat design in the Turanza EL42 RFT felt noticeably harsher when it encountered sharp-edged impacts both small and large, such as expansion joints, poorly patched pavement or minor potholes.

The conventional Potenza RE960AS also produced slightly less impact noise, with the 3G run-flat version very close behind. Again the older generation run-flat design of the Turanza EL42 RFT produced some additional booming as it hit bumps in the road.

The handling of the Potenza RE960AS 3G RFT was actually a little crisper than the non-run-flat version, taking advantage of its inherently stiffer sidewalls to help the tire change direction more briskly. The conventional Potenza RE960 was close behind, also feeling nimble and responsive. The Turanza EL42 RFT trailed the two Ultra High Performance All-Season tires, feeling somewhat less responsive as you would expect from a Standard Touring All-Season tire.

Many of our team commented on how similar the run-flat tire behaved to the conventional Potenza RE960AS Pole Position. They felt very little trade-off in everyday ride comfort and road manners when choosing the run-flat tire over the non run-flat version.

You can read the full test here.

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  • Rfritz

    As a counterpoint to this story – the Nov 28 issue of Autoweek magazine has an article on their long-term 550ix.  They’ve experienced 7 run flat tires blown out in under 19k miles.  Ouch.

    • les

      Yikes. To bad these tires cost +$1000 for my E90.

      • Evan

        Those are low-profile tires on wide rims with older tech run-flats. Since BMW supplies the car, they won’t support non-RFTs. Not that this is an excuse but this is not the norm either.

    • Mose121

      Those tires were the Goodyear LS2’s, which Goodyear has been replacing under warranty/prorate but only in the North East states.  They have never admitted that they were defective tires, and they only cover them in the NE states because they say that’s where all the pot holes are.  All Goodyear has said is that they aren’t holding up the way they would like them to and as a result they are stepping up to the plate and helping these client’s out.  Well obviously they just weren’t strong enough and it was a poor design/material selection, as I know several people who initially had to replace several tires in the first few thousand miles of ownership.  Of course they only have impact breaks when hitting a pothole, but if you breathed on them wrong they would develop sidewall bubbles.  Then Goodyear stopped producing these tires for a couple months while they redesigned the tire before it went back into production a few months ago, which to me says that the tires were garbage to begin with and they were either just a terrible design or defective.  Not to mention the pain of having to find a tire to put on your car due to this condition when there are none to be had anywhere in the country at the time. The answer is simply no; run flats have not caught up to non RFT’s.  Drive around for a day in Pittsburgh with them and you’ll come to the same conclusion.  It’s especially noticeable when going around a bend and going over a few bumps.  The entire car gets unsettled and shifts several inches to the outside of the turn.  And God forbid you have to brake while going around that bend!  Not a fun thing to experience, and certainly not something that adds to the ultimate driving experience.

  • Anonymous

    I’ll be convinced when the run-flat tires are transparent to my wallet.

  • Evan

    I just bought a set of these new generation Bridgestone RFTs after the Autoweek and TireRack reviews. They were very hard to find with all local stores quoting me months until available so I ordered from TireRack. My wife didn’t want non-RFTs because of no spare in the trunk…

    I have an E90 and the difference from the prior RFTs is incredible. The impact harshness is so much better that I still find my self wincing as I approach a bad bump with no impact. I’ll slowly get deconditioned from it.

    The difference is very striking though. The handling is better and they’re much quieter too.

    I think the RFTs in this third generation have finally hit their stride.

  • Stonect

    Please note Tire Rack is in the tire business, thus the higher the cost for tires, the more money they make, of course they will use whatever influence they have to support runflats. Runflats are a dream come true for tire companies (and tire distributors as well), they wear out fast, blow out ramdomly, come in size, performance and manufacturer profiles dedicated to certain cars (thus can’t be substituted with cheaper “no name” replacements.) My theory on runflats as far as BMW is a straight cost savings measure: the tire companies basically give away the tires to BMW in return for the replacement business (which as we know is plentiful.) BMW also saves the cost of both the spare wheel and tire, and jack for that matter. Remember what Henry Ford said: he would give away the cars if he could have 100% of the replacement part business.