Improving Aerodynamics Whilst Cycling
2007-02-23 12:20 PM | Posted by Tejvan Pettinger | Permanent Link | Time Trialling
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1 votes)
- The biggest aerodynamic drag is created from the body. If you can lower the torso you reduce aerodynamic drag significantly. It is worth spending time on trying to alter your position so that you can comfortably keep the back horizontal. Note this is not possible for everyone it depends to some extent on the natural shape of your bike. For example if look at Lance Armstrong time trialling is back is not perfectly flat. For a very good example of this position look out for pictures of Chris Boardman, especially when breaking the world hour record. To get a low back you will want to start off with a low pro frame and if necessary get an adjustable stem.
- Aero helmet. An aero helmet will make a big difference. In recent years there has been a new range of aero helmets that have also met UCI safety standards. The aerodynamic quality of these helmets has increased significantly. The important thing to look for is a suitable tail of the helmet. It is the way the air flows after the helmet that determines its aerodynamic usefulness.
- Disc Wheel. The effects of a discwheel are quite significant. They were crucial in Francesco Moser’s world record attempt in 1981 when he broke Eddy Merckx long standing hour record. In a moderate cross wind they can be even more beneficial as they work by creating a sail effect. In most competitions it is only allowed to have a disc wheel on the back. Note in very windy competitions it is advisable to avoid using a disc wheel as they increase the chance of being blown off the bike.
- Time Trial socks. Every little helps. Time trial socks or oversocks can be used to make cycling shoes more aerodynamic. The benefit is relatively small but the look good.
- Tri bars and position of arms. The use of tri bars are one of the easiest and biggest aerodynamic savings. It is estimated that the use of tri bars alone can add between 1 and 2 mph to your speed with the same power output. They work because they bring the arms inward avoiding an extra airflow resistance. To be most effective the tribars should be positioned so your arms are in line with your knees. Again there is a balance between comfort and aerodynamic benefit. If you bring them too closely together it can be more difficult to control
- Skin Suit. This is a one piece tight fitting lycra skin suit. It avoids having clothing creating aerodynamic drag it is an essential part of any time triallists equipment.
If you are just starting off time trialling start with the cheapest equipment first. The most important thing is to try and lower the position of the back. To do this may just require an adjustable stem and lower the position of the handlebars. The next most effective piece of equipment is a set of tri bars. These can be picked up relatively cheaply. I would advise buying these before moving on to disc wheels that can be very expensive for a comparative saving of effort. Also it is worth noting that in time trials weight is relatively unimportant. Don’t worry about spending hundreds of £s to save a few grams of weight, it will make little difference unless the time trial involves a lot of climbing. The most important thing is aerodynamics not weight.
