Posing
If a rider is in frame they are scale and context; the machine is the subject.
In short: If a rider is in frame they are scale and context; the machine is the subject.
Weight back, not leaning on the paint.
Relaxed and it shows the riding position.
Occupies the hands and identifies the rider.
Movement, with the machine in the foreground.
Detail with a person in it.
Camera near the ground, bike large, rider behind it.
Start with standing beside, hand on the tank — the first two minutes are warm-up and the first pose should be the one that asks least of anyone. Move to seated, feet down, looking away and helmet under the arm once the shoulders have dropped, and keep seated from low front for the end, when self-consciousness has gone. Shoot each one in bursts through the movement rather than holding it: the usable frames sit between the instructions, not on them.
Two metres back with the lens zoomed rather than close and wide — distance is what keeps facial proportions natural. Camera at or slightly above eye level for portraits, at chest height for full length. Below eye level enlarges whatever is nearest the lens, which is rarely what you want in frame.
Sitting on the bike facing the camera square-on, which flattens the machine into a silhouette of handlebars. And revving for the photograph — it produces heat shimmer and nothing else.
Shooting in bright sun. Standing too close with a wide lens, which bends the frame geometry. Forgetting to turn the front wheel. And photographing a dirty chain, which is the first thing a buyer looks at.