Where Does The Goo Go?
Lubricants and other automotive fluids are normally the slickest stuff you'll encounter on the road. Cars and trucks are the usual source of spilled fluids, though they used to leak a lot more. We were always advised to avoid the center of the road, where the oil usually fell, especially in heavy traffic areas and major intersections. That's still good advice, especially when it's wet. Heavy traffic areas that are covered-tunnels and toll booths, for example-are almost always slippery when it rains. The rain doesn't fall directly on the road surface to wash the oil away but instead drops off the wet vehicles that pass through, giving you that super-slick oil-on-water mixture. The curving tunnel at the west end of U.S. Interstate 10, which adds an off-camber turn to the equation, is a classic and scary example. Most riders will eventually encounter a toll booth on a rainy day, and if they don't remember how slick they can be, they probably will when they put their foot down or at least when they accelerate away.