Calibrating TACX Trainers and The Spin Down Calibration
The Sufferfest recommends using the TACX Utility App to do a proper spin down. The TACX Utility App will help you find the correct tire contact for your individual trainer. This is the only place where you can fine-tune your tire contact with your trainer. Tire contact is very important as it determines the amount of friction and the accuracy of your trainer. Below is a picture that shows what you will be targeting with the TACX Utility App.
The image above an example of perfect tire contact as shown in the TACX Utility App. This will give you the most reliable results when using your trainer with the Sufferfest app. You will want to check that tire pressure remains consistent each time you get on your TACX Trainer. This calibration process is not needed when using the TACX Neo or Flux as they require no spin down calibration. For the Neo and Flux, you only need the TACX Utility App to ensure your firmware from your trainer is up to date.
TACX Neo Wattage Spikes
The TACX Neo isn't power smoothed like the Wahoo KICKR. This means the Neo will bounce around the ERG target by +/- 10 watts. Any change the user makes in the cadence will have an effect on resistance applied to the NEO during ERG mode. Slight decreases in cadence will cause the Neo to increase resistance and then quickly increasing cadence will cause Wattage spikes. It very important you keep a steady and smooth pedal stroke. Below is an image that shows cadence changes by a user and the corresponding wattage spikes.
Power Spikes Due To Cadence or Effort Changes
All TACX trainers will also over achieve target wattage coming into an interval. Don't worry about shifting when you see this, just give the TACX Trainer some time to come back down into the target wattage. This could take up to 3 seconds. If you find this to be too annoying or bothersome, then we suggest doing the workout in a level mode where you can shift gears to hit your targets.
Can't Hit Recovery Targets
The minions are asked about this quite a bit at Sufferlandrian Services. The rider has a recovery wattage of 125 watts. However, their trainer won't go below 150 watts. What is going on? We will show you exactly what is going on. Below is an image of a TACX Vortex Smart being used with the Sufferfest Training Centre.
Do you see that bump in wattage that we are reporting? That is strictly due to wheel speed. All trainers have a wattage line that dictates minimum power output. That wattage output is purely influenced by wheel speed. Look at our next image below of the virtual power curve of the TACX Vortex Smart that is not connected to anything.
A rider cannot go below that red line. So, if you are trying to hit 125 watts, but your wheel speed is 40kph, then you need to shift up a few gears. Slowing wheel speed will help get you to your recovery targets. This is often seen with mid-range and budget trainers; they still need to be shifted to hit the lower wattage numbers.