Corrugations
What are corrugations? They are known as washboards in the U.S. I have had several english people ask me what they are. So Crank (Thank You) kindly went out and found some and photographed them for you. Knowing what they are, you can prepare yourself if you are ever going to ride over them. Photographs kindly provided by crank.
Corrugations form on gravel roads by the action of water and traffic. Driving a vehicle over them at speed results in a bone jarring ride. Riding a fully loaded bicycle over them also takes it's toll. Plastic water bottles crack, hence the warning about not putting all of your water in one container. It can also take a toll on the rider, and the bicycle, especially the frame and racks.
The size of the corrugations can also vary, and be very close like the corrugations found in the corrugated iron used for roofing, or further apart. The photos below illustrate a gravel road with some corrugations.
Typical view of a corrugated gravel road.
Photo 1 Is a close up typical corrugations on a gravel road. Most councils grade the roads at certain times of the year and this removes the corrugations. Some gravel roads have their entire lengths full of corrugations such as these. A mountain bike with it's wider tyres has some degree of padding against the jarring, but a road bike with it's narrow tyres won't stand up to riding too far on a road such as this.
Another view of a typical corrugated road.
A close up of some corrugations on a typical gravel road.
Photo 2 shows a different view of some more corrugations. When riding on a heavily corrugated road, it is easy to pick a path out around the corrugations. There are two things to be wary of when doing this. One is to listen out for traffic, which you can sometimes not hear, and the other is that some roads contain large patches of sand or gravel dust (also called bull dust) which results in your bike coming to a sudden halt as it's wheels sink into the sand.
In photo 2, you could pick a line up the centre of the road from the camera's point of view, but you would still hit some corrugations. Being careful it is possible to weave around them and create a somewhat smoother ride. Photo 3 shows a close up of wider corrugations and the piles of dust on the road.
When riding on roads like this, there is another problem. When a vehicle passes in dry weather, it leaves a cloud of dust, which leaves you choking. WARNING! If there is a second vehicle behind it, it will NOT SEE you. It is best to stay off of the road until the dust clears. Sometimes in the outback where it is flat you can see a vehicle coming by the cloud of dust that it leaves behind. A good idea is to put a handkerchief around your face to stop having to breath the dust.
