Training Tacx Films
- 10 - 16 oktober 2013
Working ranges
When the current value is displayed in red, it means you are not actually performing as indicated at
that time. Because the trainer’s roll will not turn by itself during a descent in the terrain, like it
would in real life, the software contains ‘virtual speed formulas’. In order to imitate reality as much
as possible, the rider’s speed is artificially increased during descents and decreased uphill. As a
result of this application, the speed indicated on the screen will in many cases differ from the actual
riding speed. This is indicated in the training data by means of red numbers for speed.
Regardless which trainer you buy, it is Tacx’s goal to offer the same work-out on each trainer when
you climb a mountain. Whether you do this on an i- Flow or an i-Genius, in the end the amount of
energy delivered by the rider should be the same. This is complicated, because the braking power of
the i-Flow is not the same as the braking power of the i-Genius. The i-Genius can deal with much
more power. So an 8% slope feels different on the i-Flow (light) than on the i-Genius (heavy, the full
8%), because the i-Genius is much better in simulating a climb. On the i-Flow, the braking stops
around 4-5% (depending on the weight settings).
To reach our main goal, we need to change something in our software, to make sure that the work-
out is the same in the end. This we achieve by reducing the speed of the i-Flow the moment the
maximum braking power is reached. The displayed speed is shown in red in the software (or it is
shown square on the i-Vortex or Bushido). This is what we call virtual speed.
The main difference
Knowing this, it is easier to understand the main difference between the Tacx trainers:
i-Flow
The i-Flow can brake to a maximum of 4-5% depending on your weight settings. Above this
maximum the speed will go down, so you will not experience the actual cycling speed. Climbing at
8% will never feel real.
The i-Flow comes with the Basic version of the Tacx Trainer software 4. This means that certain
functions (like import, export and VR) are not fully available.
i-Vortex
The i-Vortex can brake to a maximum of around 7% depending on your weight settings. It works
almost the same as the i-Flow, the difference being that the % can be spread more evenly over the
resistance power. This means for example that 4% slope will feel like a 3% climb, 6% slope will feel
like a 4% climb and 9% slope will feel like a 6% climb.
Bushido
The Bushido has more braking power than the i-Vortex. This means for example that 11% slope will
feel like an 8% climb.
i-Genius
The i-Genius can go up to 20%. There is no braking manipulation, which means that cycling on the i-
Genius will feel much more realistic.
Other differences
In addition to the above, there are some other differences between the Tacx trainers: