February 7, 2012
Instructors Philippe Letourneau and Sylvain Champoux (top); Getting instructions before hitting the course (bottom). Click image to enlarge
All tires wear, of course, and for the hard-packed course, we were driving on a series of winter tires that were worn to 4/32nds of their tread – 2/32nds being the legal road limit. This was primarily to show off the X-Ice’s longevity, since the company has a limited tread wear guarantee of 60,000 km. Most notably, the sipes – the tiny slits in the tread blocks, which help provide traction and water evacuation – were still in the treads, whereas they were mostly worn off on the competition. But from a purely educational standpoint, the driving exercise helped teach me how to “read” the tire through the steering wheel. Because of their wear patterns, each tire had slightly different characteristics: one had less lateral stability, one didn’t grip as firmly on acceleration, and another took longer to stop. As soon as I felt each tire underperform in a specific situation, I knew I had to adjust my driving, such as taking turns slower or allowing more time to stop. Safe drivers don’t drive like robots. Instead, they constantly monitor how the car feels and reacts to determine if the road has become slippery or greasy. They then change their driving habits to suit those conditions.
You might not realize just how quickly road conditions can change, which we discovered when our group was sent to the ice acceleration and braking portion. It was indeed glare ice, and it was difficult just to get in and out of the cars without slipping. Each driver had to accelerate at full throttle, modulate the car’s speed to 25 km/h and, at a specific point, jam on the brakes. The X-Ice tires stopped the soonest, of course – it was a Michelin event, after all – but we noticed that, as all the drivers ran through the course, our stopping distances varied slightly even on the same brand of tire. The reason, our instructor told us, was the weather. During the short time we were on the course the sun came out, which was just enough to create a thin film of water on the ice. A cold wind then picked up, freezing it again. As minor as that sounds, it made a difference, and so does that constant monitoring of what’s under the wheels.
Hitting the brakes on the ice course (top); the result of a day of driving on the snowy course (bottom). Click image to enlarge
Our final run was that combination course, using front-wheel, all-wheel and rear-wheel drive vehicles. This course was constantly changing as vehicles went over it and exposed more ice. “Find the grip,” was the instruction, and that meant looking for areas that had some snow cover where our tires could bite in. Whenever possible, look for the uncharted course when you’re driving, to avoid spots where other cars have uncovered the icy underside. “Everyone comes up to the stop sign in the same place,” our instructor said. “You know that’s where it will be slippery, so you try to stay away from it.” He was right: once I strayed just a few centimetres from the ruts where other vehicles had worn the snow away, my car stopped much sooner.
I flew home that night, facing an 80-kilometre drive home from the airport. There was a bit of snow on the highway and more started falling as I drove east. Putting into play what I’d learned, I paid close attention to the road, reading the news the steering wheel was sending from the tires. I also listened for changes in road noise that could indicate variations on the surface. Not far from home, I hit that great Canadian fear, a patch of black ice. The low temperature indicated a good chance of this thin icy film forming, and I knew I’d found some when I suddenly felt some “float” from my tires. Keeping my speed constant and the steering wheel straight ahead got me safely over it and back onto asphalt that was just snowy, but I didn’t let down my guard until I was under my carport at home. Good tires, good training and paying attention: if drivers are prepared, winter doesn’t stand a chance.
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