Big Wheels Run Flat

big wheels run flat
As I’ve aged, I’ve begun to notice that certain carmakers are determined to enrich chiropractors and practitioners of restorative dentistry. When driving my Nissan 350Z, I found myself avoiding pockmarked roads for fear of ceiling-related spinal compression. Even on smooth roads, I couldn’t quaff carbonated beverages. Since then, I’ve created a checklist of cars my increasingly fragile skeletal system cannot abide. This includes the aforementioned Z, the Acura TL, pretty much any Infiniti or Porsche product, the S4 and S6 Audis and the Lexus SC430. There is a special sub-category— torture– reserved for the vehicles made by BMW equipped with run-flat tires.

I understand the concept behind run-flat tires. Changing a flat on the side of the highway is only slightly less dangerous than marshalling at an Estonian track day. Since most people pull over at the first whup-whup, run-flat tires could be a life saver. Drivers can reach service without the need to sit on the side of the road and pray that drunk, fatigued and inattentive drivers have already found a safe place to crash. And then there’s the complexity and the mess. I personally have no problem jacking my own car (it’s getting the jack re-stowed that puzzles me), but there’s no way to change a tire without ending up with the tire stats imprinted on your clothing.

Run-flat tires are fine in theory. In practice, at least as applied by the Bavarians, it destroys all hope of a luxurious ride. I’ve sampled the BMW 645, 545, 650 IC and 330 with run-flat tires. Every single one was harsh riding: introducing an unacceptable amount of impact-related violence to otherwise stable suspension and solid chassis. And that’s without discussing the stiff sidewalls’ numbing effect on BMW’s formerly sublime steering, on top of the automotive Novocain BMW calls Active Steering. In any case, compound run-flat fatigue with nineteen inch wheels (sport package) and there you have it: the ultimate punishing machine.

German car lovers often shake their heads knowingly and point out that Bimmer’s backyard is also the original home of the billiard table road. I’ve been to Germany often. And it’s true; find a twisting two-lane road in the Bavarian countryside and you’ll be traversing a surface as smooth as a supermodel’s epidermis. But it’s also true that the roads in and around Munich, and throughout the formerly communist eastern part of the country, are marred by potholes and bumps. No; I think it’s down to age-related snobbery.

Perhaps BMW believes that once a potential customer turns 50, the tipping point where enthusiasts are suddenly willing to trade razor-sharp handling for long-distance commuter comfort, they should be earning enough money to afford their more expensive models. This would explain why Bimmer’s most costly cars– the 750, M5 and M6– don’t sport run-flats. Of course, that theory wouldn’t explain the fact that the 7-Series was the first BMW model to include the pre-Boomer’s worst nightmare: the iDrive mouse-driven multi-infuriating controller. But it’s possible that BMW’s left hand doesn’t know what the right hand is doing— which is about as good a description of iDrive as I can provide.

This run-flat torment is not the roundel’s exclusive domain, but they have certainly perfected the torture. RF tells me that tire technology is evolving; that the 325i is not so bad, and that the comfort – handling nexus will eventually be sorted. For the time being, nothing beats installing a couple of pairs of proper summer and winter shoes. But I’m not happy buying a brand new car only to throw out (or wait out) the OEM tires for something that should have been installed from the git-go.

Meanwhile, I’m struggling to understand why we need wheels larger than 17” for street use. As I drive down the highway next to a youngish person driving a Chrysler 300 with double dubs, I notice how the driver looks bobble headed as their car impacts abruptly over the slightest road imperfections. What is the point of this? At the risk of pissing off at least three separate demographic groups, I blame women for both trends.

My wife loves the idea of run-flat tires. In fact, she thinks all tires are run-flat capable (which explains why every flat tire in my house is accompanied by the need for both a new tire and a new wheel). In addition, my wife doesn’t complain about the deterioration in ride quality from run-flat tires. I suspect her tolerance for auto-related physical abuse is related to her reasoning for wearing shoes (especially high heels) that “look fantastic” but eventually, inevitably, hurt like Hell. So let’s make those twenty two inch run-flat tires standard equipment on all the chick cars and let me have my seventeens and some Michelin Pilots and call it a day.

Comments
Join the conversation
2 of 20 comments
  • Ian Jordan Ian Jordan on Jul 06, 2006

    Air guns can't control torque. The only right way to torque a lugnut is with a hand torque wench. The reason for larger wheels on sports cars is brakes. You need bigger wheels to fit bigger and bigger brakes. My RX-8 won't fit anything smaller than the factory 18" wheels due to the brake diameter. Factory run-flats always have tire pressure monitoring systems, due to the fact that it's hard on the highway to tell you have a flat from the feel of the car. Pretty hard to drive along "not knowing" when there's a big yellow light blinking at you.

  • Niky Niky on Jul 13, 2006

    You may need a big wheel for big brakes, but you certainly don't need a heavy wheel. Shame on rappers for making everyone think rubber bands on solid chrome hoops are cool. And double shame on automakers for making wheel wells so large that sensible wheels won't fill them anymore... forcing more people to buy said chrome hoops. These two factors have increased our annual oil consumption by at least a few million barrels, don't you think? I'm in agreement with Homourless up there: even 17's are too big for compact cars. 15's, with the right tires, will give you more compliance, a better ride, nearly the same grip (just get better tires) and won't suffer catastrophic damage over potholes. I've got a car on 17's and a beater (for work) on 13's. I've had lots more fun in the second one, despite the total lack of grip. Heck, I believe 90% of speed-related road fatalities can be prevented by sticking the smallest wheels possible on each new car, with the narrowest rubber. Everyone will be sliding around at 15 mph, having a grand old time, and too busy trying to stay in control to get close to 100.

  • Bobbysirhan After massive bus fire, CT pulls electric fleet from service (middletownpress.com)At least they're following the science.
  • SPPPP I got a kick out of the three paragraphs beginning with "As a reminder..." and ending with "straight(ish) line". In no small part because they showed up twice in the article. As I scrolled past the next picture, I was gleefully excited to see if they would show up a third time. But no, the rest of the article continued as normal. Competent though it was, the magic was gone.
  • SPPPP Just an observation - at $1.66 billion for a target 1,800 buses, that's $922,222.22 per bus. I know they will need chargers, but still ... doesn't that seem pretty un-ambitious? Couldn't they put more than 20,000 Ford E-transit electric vans on the streets for the same price?
  • Kosmo The power figures for the 3.0 diesel are impressive, especially compared to the 3.0 diesel in our 2007 Sprinter.(Ralph Nader enters room) How do those STEEL bumpers affect crash safety?
  • Kosmo Magnum Wagon reboot would be the schizzle!
Next