By Chris Carmichael
Tom Boonen just can’t catch a break. The former World Champion and green jersey winner, the guy who just won the Belgian National Championship the week before the Tour de France, has yet to factor into a single stage finish. In Stage 2 he was forced off course by a crash about 700 meters from the line. The next day he didn’t make the front group when Columbia-HTC split the field in heavy crosswinds, and hence missed out on the sprint finish. During Stage 5, he suffered a flat tire just as the pack was splitting up in strong crosswinds, rode his way back into the peloton, and then promptly flatted again. Although he managed to get back in the field, he was not a factor in the sprint for third place (behind stage winner Thomas Voekler and one more surviving breakaway rider). So today, on the sixth stage of the 2009 Tour de France, perhaps it would be his lucky day. But not so much. This time he ended up crashing on the wet and slippery streets of Barcelona, Spain a few kilometers from the finish.
Rain always wreaks havoc on the peloton, but one of the worst scenarios is a combination of rain and city streets. Given the same rain conditions, racing through the countryside on wet roads is almost always safer than racing through a big city. With the increased car traffic on urban roads there’s more oil on the surface of the street. It’s been hot and dry in Barcelona for the past several days, so there’s been plenty of time for oil to build up, too. And when it rained today, it wasn’t a flooding downpour that was strong enough to significantly wash away the oil, so it stayed on top of the water and made the roads incredibly slippery.
Urban areas also have a lot more paint on the roads (cross-walks, directional arrows, lane lines, etc.) and a lot more manhole covers. When you put oily water on top of road paint or steel, the result is a surface that’s as slippery as ice. The crashes we saw in roundabouts on the way into Barcelona today (like the one that sent Garmin-Slipstream’s Tyler Farrar over a barrier and injured Columbia HTC’s Michael Rogers) were likely the result of the oily water on top of the pavement. The later crashes in town, though, including the one that took Boonen out of contention for the stage win, appeared to be caused by road paint.
Roundabouts? It's hard not to hold your breath...while watching the race.
In any situation where you know your traction will be compromised, there are three primary ways to improve your chances of staying upright: adjust your speed, keep the bike upright, and stay off the brakes. Ideally, avoiding road paint is your best bet, but while racing in a pack that’s not always realistic. When you have to cross the paint or the manhole covers, you want your bike to be as upright as possible instead of being leaned over. As you lean into a corner, you’re relying on the friction between your tire and the road to keep your wheels from sliding out. Rain, paint, and/or metal reduce that friction and put you in a situation where just a little bit of sideways force will be enough to break your tires loose. Keeping the bike more upright keeps your center of gravity closer to the midline of your bike, which helps to maximize your traction in slippery conditions.
However, even with your bike more upright, there’s still less traction on slippery roads and road paint. High-speed cornering is entirely dependent on your tires staying in contact with the road, so it stands to reason that reduced traction puts a limit on how fast you can go through a corner without falling. But adjusting your speed in order to make it safely through a corner can cause just as much trouble as the corner itself. Your wheels are much quicker to lock up and slide when the roads are wet or if you’re riding over paint. One of the worst situations for racers is to be in the middle of the pack, braking before a corner on black pavement, and then rolling onto a painted crosswalk while you’re still on the brakes. In an instant, and owing only the change in the surface below your tires, your wheels lock up and you’re sliding. If you’re lucky, you can keep it upright long enough to get back onto black pavement and regain control. If you’re unlucky, you’re on the ground before you know what happened.
If you see the scenario above developing in front of you, the best thing you can try to do is change your line slightly so you can cross the paint while still going straight, and release your brakes just before you hit the paint. This will help keep your tires rolling over the paint instead of sliding. The risky part of this technique is that if you failed to control your speed adequately before reaching the paint, and then you release the brakes to roll across it, you may then have to brake hard as soon as you get back onto black pavement. The problem is, that pavement is wet too, and hard braking may be enough to cause you to slide anyway.
With so many riders doing their best to either hold or advance position, it's no wonder that wet roads can wreak havoc.
At the end of the day, staying upright in the rain takes a combination of luck and practice. Like everyone else, I’d rather ride in warm sun than cold rain, but it’s important to realize that there are benefits to occasionally getting caught in the rain – or even starting out in the rain. Training in the rain allows you to be conservative with your speed at first and then gain the confidence to start going faster. It helps to teach you how differently your brakes work when your wheels and brake pads are wet. For racers, it’s crucial to be comfortable and confident in the rain, because nervousness leads to a tight grip on the bars and tension in your arms and shoulders. In slippery conditions, that makes it even more likely that you’re going to hit the deck.
With the possible exception of Tom Boonen, it doesn’t appear that the rain significantly impacted the actual finishing order of Stage 6 of the 2009 Tour de France. With the help of a gradual climb over the final 1-2 kilometers of the stage, Cervelo’s Thor Hushovd finally got the better of Columbia-HTC’s Mark Cavendish. The climb was also good for keeping the riders safe because the speeds were lower than they would have been in the final two kilometers of a flat run-in to the finish. Lance Armstrong and all the yellow jersey contenders finished in the main peloton, and now they’re looking forward to tomorrow’s first rendezvous with the mountains.
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Chris Carmichael has been Lance Armstrong’s coach for 20 years and is the founder of Carmichael Training Systems (CTS). For more information on CTS’ Create Your Own Comeback program, the free Do the Tour...Stay at Home™ training program, and the free CTS Tour de France Newsletter, visit www.trainright.com. You can also follow Chris on Twitter.
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