Introduction The Position Simulator has been developed to round off the Bikefitting.com Standard analysis. This device is very unique because you can determine exactly the right seat-angle. The measurement of the seat angle is rather complex but due to the Position Simulator it is very easy to determine. In one handling you can measure the proportion upperleg length and underleg length by taking into account the influence which the saddle height and the position on the saddle have on the correct seat angle. The functions of the Position Simulator are as follows: measurement of the correct seat angle as a condition for an optimal transmission of power during cycling. measurement of an asymmetric position on the bicycle. the cyclist can immediately experience the position which Bikefitting.com is advising.
Theory To optimize the cycling motion of the physical locomotion there are five parameters: Anatomical saddle middle 1 Anatomical saddle middle 2 Saddle height 3 Crank length 4 Position of the shoe cleats 5 Seat angle Physical locomotion Seat angle The correct sizes and adjustments of the data 1 to 3 are the result of the Bikefitting.com Standard computer analysis. Position 4 is the result of the Shoe Cleat Adjuster measurement.to determine the correct seat angle (position 5) the Position Simulator and the Professional online software have been developed especiallly. Saddle height Crank length
Contrary to common belief, it is not possible to determine the correct seat angle through the proportion of underleg - upperleg. First of all it is almost impossible to measure this proportion exactly and, secondly, the saddle height and the position of the cyclist on the saddle have an effect on the correct seat angle. In accordance with theory the point where the power of the upper leg goes into the under leg has to be above the centre of the pedal axle when crank and pedal are horizontal. It not only gives a correct fluency of power but also has an effect on the position on the saddle. If the power transmission of the movement locomotion and the pedal mechanism of the bicycle are not in one line then the result will be a very unrestful position on the saddle, which can lead to lost efficiency. Position of the shoe cleats
Procedure The measurement with the Position Simulator is an addition to the Standard online computer measurement. The cyclist should be dressed in her/him cyclist outfit. You will get the best results when the measurement is taken with the cyclist s own saddle and the pedal system, or, in case of a new bike, with the manufacturer s saddle and pedal system. As explained earlier, the position on the saddle has an effect on the correct seat angle. Before we start with the procedure of the adjustment of the Position Simulator, four important points need to be taken into account. 1 After the Position Simulator is adjusted, the cyclist should cycle a few minutes to find the right position on the saddle. Make sure that this position is kept during the whole measurement. 2 The hands are on the handle bar (check the adjustment of the stem). 3 It is not necessary to adjust the shoe cleats before the measurement. 4 Adjust the resistance unit in such a way that the cyclist can easily pedal with a feeling of resistance.
Step 1 Adjust the seat angle at the standard 73.5 degrees angle. An exception is the Time Trial Triathlon analysis with a seat angle of 78.0 degrees. The seat angle can be adjusted with the black nut below of the top tube. seat angle black nut resistance unit
Step 2 Mount the saddle in a horizontal position and place the anatomic middle of the saddle into the centre of the seatpost tube by means of the saddle centring device. anatomical saddle middle saddle centring device
Step 3 Adjust the saddle height in accordance with the coordinate of the Professional online measurement. The saddle height is the distance from the axle centre to the top of the anatomical saddle middle. The saddle height can be adjusted with the Saddle Height Adjuster. anatomical saddle middle saddle height axle centre
Step 4 Adjust the stem height in accordance with the coordinate of the Professional online measurement program. This size needs to be read at the top of the stem holder. top of the stem holder
Step 5 Adjust the stem length in accordance with the coordinate of the Professional online measurement program. This size needs to be read on the cyclist s side of the grey handlebar holder. cyclist s side handlebar holder
Step 6 When the cyclist has taken a seat on the Position Simulator the actual measurement can start. 1 The hands are positioned on the break levers. 2 The shoes are locked into the pedal system. 3 After having found the correct position on the saddle, it is important that the cyclist stays in this position during the whole measurement. 4 The left crank should be fixed by placing the locking pin through the hole in the crank into the fixation pipe of the vertical tube. 5 The left pedal should be fixed in a horizontal position. 6 The knee stop should be placed in and against the holder on the horizontal tube. Furthermore, the knee stop should be turned into the direction of the front of the knee. 7 If the stop is behind or in front of the knee, the black nut should be turned in such a way that the front of the knee and the brass knee stop are in connection with each other. 8 Repeat point 4 to 7 for the right knee. 9 If there is a difference between the left and right knee position, you have to take the average of both measurements. 10 Read the seat angle at the end of the horizontal outside tube and type the data into the Professional online program and compute the custom drawing.
knee stop seat angle knee-pedal-axle-line crank and pedal are horizontal