On the straight, your goal is to offer the smallest drag you can. The two ways to do that -- which cooperate in terms of the rider position -- are to reduce the frontal area and to smooth the airflow.
Reducing the frontal area has been understood for at least a century. Crouch down on the bike, bury your head behind the gauges, lie down over the tank -- riders have been doing that forever. It's still what you need to do on an unfaired bike. Just remember you still have to have your arms loose, you still have to be able to see, and you still have to be able to control the bike.
With a faired bike, the method is slightly different. You want to be not only tucked down behind the screen, but you want to present a smooth profile for the air to flow off the screen, over your back, and on to the tailsection. So you don't want to be totally out of the airflow, you want to become part of the shape of the bike.
In this photograph from a WERA race at NCMS some years back, the rider is well tucked in behind the fairing. Her elbows and knees are out of the airflow while still retaining control of the bike, and the air flows smoothly over the screen, and with the rider low on the tank the airflow is smoothed from the rider's back across the tail section of the bike.
Photo by Martyn WheelerAgain, bear in mind that the priority is to control the bike. All the speed in the world will do no good if you run into the starter's stand. Remember also that some steep front-end geometry can start to wobble if you put too much weight on the front, so don't overdo it. But every little bit you can do to reduce the drag is squared in effect.
From TrackDoD Novice Group Orientation
No comments:
Post a Comment