Body scanning

What is the perfect riding position for me? And which frame size is the right one? Every body is unique, which is why your bike needs individual adjustments. 

To ensure that your bike optimally suits your physique, adjusting things like saddle height and the position of the handlebars is crucial. An efficient way to get the fit and setup right is to use a body scanning system.

Find out how body scanning works, which measurements are taken, and where SIMPLON uses the 360-degree body scanner!

What is body scanning?

Body scanning is a 3D body analysis system. With the help of this 360-degree system, even the most minute imbalances can be detected. The results of the analysis serve as the basis for finding the right bike fit and setup.

The precise system was developed by orthopaedists, physiotherapists, cyclists, and engineers.

Why is body scanning useful?

The advantages of 3D body scanning are obvious: By adjusting things like 

• the height and position of the saddle,
• the saddle-to-handlebar distance,
• the handlebar position,
• the frame size,
• and the length of the cranks,

power transfer is optimised, and health risks are reduced. 

A convex shape of the bicycle saddle contributes to better ergonomics: It can reduce pressure on the soft tissues below the pubic arch.

Adjusting the handlebars or grips to fit the body can reduce strain on the hands and fingers. If you have carpal tunnel syndrome, for instance, you should pay particular attention to the angle between your hand and forearm. Bikers who have problems in the area of their two little fingers can achieve improvements by adjusting the size and shape of the grips.

What does the body scanning process look like?

The first step is to get into the right position. Once the scanning process begins, it is important to keep still. That’s the only way to get a precise measurement without distortions. 

Biometric data such as the functional height of the rider, the last cervical vertebra (C7 prominent), the top of the hip bone (iliac crest) and other “landmarks” are recorded. Body measurements such as the circumference and height of the waist, arm and inside leg length as well as hand length and the distance between the two sit bones are taken. 

The latter, along with the riding position, is a decisive factor for perfect saddle ergonomics. Body scanning allows for an exact and case-specific adjustment of the saddle. 

Good to know: There are no contraindications for pregnant women or people with pacemakers when it comes to using a body scanner.

Bicycle adjustments after body scanning

Once all the required measurements have been recorded, the next step is to adjust the bike to the rider's individual anatomy and riding style.

Setting the saddle height

Let’s start with saddle height. Using an adjustment gauge, the distance from the centre of the crank bolt to the upper edge of the saddle is measured and adjusted accordingly. 

Note: If you have an ergonomic step saddle, you should measure the distance up to the top of the step.

Optimising saddle setback

Then it’s time to adjust the saddle setback or saddle position. This is crucial for a good pedalling feel and optimum power transfer between the bike and rider. For the adjustment, the distance in vertical direction through the bottom bracket axle to the saddle nose gets measured.

Important: When determining the distance, it is important that the foot is correctly positioned on the pedal. The ball of the foot should be positioned exactly above the pedal axle. 

Adjusting the saddle-to-handlebar distance 

In order to optimally adjust the distance between the saddle and the handlebars, the length of the upper body and the sitting position must be taken into account. The distance from the nose of the saddle to a certain point on the handlebars gets measured. This point depends on the type of bike you ride. On road bikes, you measure the distance between the nose of the saddle and the grip of the handlebar. On mountain bikes with straight handlebars, you measure the distance from the nose of the saddle to the top of the handlebar. The number you get often determines the length of the bicycle frame.

Improving handlebar position

The handlebar position is determined by the relation between the handlebars and saddle. The tolerance field is relatively large in this case. In theory, there are only three riding positions: relaxed, moderate, and athletic. However, practice shows that there are numerous other positions in between. Here, too, the measurement gets taken with the adjustment gauge.

Finding the right frame height

The three contact points (handlebars, saddle, and pedals) where the rider touches the bike are of central importance when it comes to frame height. For bikes with a sloping top tube and a suspension seatpost, the top tube length is crucial when taking measurements. Optimal alignment of the frame ensures ergonomic comfort.

Choosing the ideal crank length

The longer the crank, the more torque you get – which in turn transfers over to the bottom bracket axle. A jump from 175 millimetres to 177.5 millimetres increases the torque by 1.5 percent. But keep in mind: A longer crank improves the efficiency only in principle. In practice, the motor skills and leg length of the rider also need to be taken into account. In mountain biking, ground clearance is an additional factor.

Depending on the type of bike, cranks come in certain standard lengths:

Mountain bikes: maximum 175 millimetres
Trekking and city bikes: maximum 170 millimetres
Road bikes: between 165 and 180 millimetres

Adjusting the riding position

The ideal ergonomics are different for every rider and also depend on his or her riding preferences. If you are cycling in urban areas, the ergonomics are geared towards a more relaxed sitting position. It should be easy for you to get on and off the bike whenever you stop at a traffic light. 

For road cyclists, the focus is on an aerodynamic sitting position, which allows them to achieve a high cadence and pedalling efficiency.