Wednesday, January 4, 2012 03:05
Many times I have written that buying used tires is God’s way of saying, “You suck at managing money, you’re a hazard on the highway and we might soon meet in person.” However, I just bought two used tires.
BFGoodrich made me do it. Kind of. Also at fault: front-wheel drive and the failure of the car’s most-frequent driver (and her daddy) to be diligent about tire rotation.
A front-wheel-drive vehicle wears out its front tires much more quickly than its rears. Why? Because the fronts carry almost two-thirds of the vehicle’s weight, does all of the steering, 80 percent of the braking and all of the acceleration. The rear tires’ main job is to keep the gas tank from dragging on the pavement. Fail to frequently rotate tires and you’ll wind up with almost-new rear tires and half-worn front tires. It’s dangerous to put the near-new tires on the front and half-worn ones on the rear. Put newer tires on the rear.
I “had” to buy two used tires because BFG no longer offers the Traction T/A SPEC in P215/65R16. I could not meet my requirement of EXACTLY matching the rear tires, right down to the part number. The rears had plenty of tread: 7/32nds-inch. I’m cheap, but cautious and serious about safety: Tires come off my cars at 4/32nds-inch. More...
Thursday, December 8, 2011 02:12
At the recent Tokyo Auto Show, Bridgestone unveiled a non-pneumatic “tire” very similar to the Michelin Tweel, which debuted with much unwarranted fanfare several years ago. You’ll NEVER see either on a production automobile. Okay, maybe on a flying car, not before.
To Bridgestone’s credit, it said the tire/wheel combo was intended for golf carts and the like. As it was accepting innovation awards and being featured in the New York Times and on the cover of Time magazine, Michelin said the Tweel would be on production vehicles by 2015. I’m one of few to have driven a Tweel on a passenger car. (That’s me behind the wheel in the Michelin PR photos.) When I heard the “in 10 years” prediction, I tried to bet against that with Michelin folks. I started at $100,000 and progressively reduced the proposed bet. None would bet even $1. More...
Tuesday, November 22, 2011 06:00
I like connector ramps, on-ramps, off-ramps, merges, big curves, twisties, switchbacks, anything that allows me to sling myself through a turn at rates beyond the acceptable. My friends call it the slice and dice, and they’re right—driving should be fun. Commuting through traffic on a sticky set of DOT-legal race tires makes it even more fun.
Alright, technically the Dunlop Z1 isn’t a race tire, but it is a tire that folks race with—autocrossers, track-day killers, and canyon carvers alike have called it a marvel. When the Z1 was approved as an SCCA-legal item, it was highly sought after, even more so when the Z1 Star Spec was introduced, a slight redesign of the original Z1 that sorted out the first tire’s tendency to warm up too slowly for short-course autocrossing (and brought an added benefit of slightly improved threshold grip). The point is that the Dunlop Z1, even four-plus years after its release to the American public, is a big-G knife, paws for the wolves in sheep’s traffic.
The Z1’s American availability is a sticky wicket in its own right. Dunlop, as we all remember from race tires in Europe, motorcycles, Le Mans, and so many other bits of awesome from the good old days, is no longer, having been broken up and sold to the Japanese (Sumitomo) and Americans (Goodyear). Fortunately, both parent companies share lots of the development and promotional duties, and different Dunlops pass back and forth between them for availability in the U.S. For example, the Dunlop SportMaxx, a big-sedan Euro-style Autobahn killer (ideal for everything from G8 to M5), is made by the Goodyear Dunlop, while the Direzza DZ101 rice-racer favorite and the slightly related Z1 are made by the Japanese Dunlop (and is at-home with the all-wheel drive and Porsche crowd). Indeed, the Japanese get a few other versions of the Z1 that are even racier than the Z1 Star Spec over here, but at least we have that, because it’s super. More...
Tuesday, October 11, 2011 09:42
I was riding in the right-front seat of an old Cadillac when the right-rear tire tread left its assigned position. Still partially attached to the tire, the tread whipped by my right ear like a giant, steel-reinforced Weed Whacker string.
The flailing tread cleaned off the outside mirror, door handle and door trim in the first couple of passes. Then it smashed the rear passenger window. I knew tire-tread separations were dangerous, but I had focused more on the potential loss of control than the havoc it can cause immediately upon the separation.
This was in a controlled environment. We were doing a demonstration for a tire company, allowing people to experience a tread separation from behind the wheel. The tires were cut in a manner to ensure a quick separation. Fortunately, the car had its inner fender panels reinforced with armor plating, which kept that tread from slicing into the passenger compartment. After the run we stopped allowing people to ride in the right-rear seat during demos.
I’ve described how to survive a blowout and the basics of tread separations. This is a bit more on tread separations. For those too lazy to click there and back, here’s a quick primer: A tread separation is when a tire’s tread and belt package departs from the tire carcass. Tread separations are far more common than true blowouts and many tread separations are incorrectly called blowouts. Those “road gators” from 18-wheelers strewn alongside Southern highways in the summer are almost all tread separations and not recap failures. More...
Monday, October 3, 2011 08:00
It’s easy to argue that a tire tread separation is even more dangerous than a blowout. Neither need to result in disaster it you know how to handle the emergency. (Read: How to Survive a Blowout.)
The main reason: It’s almost impossible to fail to notice a true blowout. A true blowout sounds almost like a gunshot and the road wheel makes a horrible grinding noise as it rides directly on the pavement. I guess you can play Lynyrd Skynyrd’s “Freebird” loud enough to overcome these noises, but it’s impossible to ignore the fact that the vehicle—especially an SUV or pickup—drops several inches when the tire instantly deflates.
Tread separations, which are more common than true blowouts, act in the opposite manner. (First, a definition: A tread separation is when the tire tread departs from the tire casing. Those truck-tire “road gators” strewn alongside the road are almost all tread separations rather than failed recaps.
Prior to a tread separation, an attentive driver will notice a light slapping noise and possibly an uneven ride. Things change when the baby road gator is about to be born. The tread will start slapping the inner fender panel with a hammering racket. If the tread flies off quickly, the noise stops and the car will ride smoothly again. The ignorant or overly optimistic may think the tire has magically cured itself. The truth: The tire is now a time bomb. With the tread gone, the tire’s fabric inner carcass is the only thing touching the road. That fabric provides almost no traction, so if you turn the wheel the car will either spin out or plow straight off the corner. Sooner or later, the fabric will fail and the tire will deflate, perhaps even blow out.
A tread separation can cause other damage, including ripping through the inner fender and slicing through human flesh. With that happy thought, we’ll leave you and return another day with tips on how to handle and prevent a tread separation.