A wheel-on smart trainer is an affordable alternative to a direct drive trainer. However, there are special steps that are needed to ensure that they are accurate and consistent.
Slight variations in tire pressure, or in tension applied to the wheel, can increase or decrease the power reported to the app. To ensure that your power is always measured consistently and accurately, you will need to check your tire pressure and perform the spin down calibration prior to every ride.
The spin-down calibration needs to be completed in the trainer's native app. (ex: Wahoo trainers use the Wahoo app, Tacx trainers use the Tacx app). Be sure that your trainer is properly warmed up, as tire pressure will change once the tire is properly warmed. Be sure that your spindown time or numbers are within the trainer's acceptable limits (check your user manual), and that they are consistently the same. Variations in spin-down time, even within the allowable limits may affect the degree of accuracy for your trainer.
We recommend the use of a trainer specific tire to prevent slipping.
Please keep in mind that the trainer response time on a wheel-on smart trainer may be longer than a direct drive trainer. It is considered normal to have a 5-10 second lag time between the start of an interval and the time it takes your trainer to reach the target power. We recommend keeping your cadence steady and smooth until the trainer reaches the target power and then smoothly and gradually adjusting your cadence to the cadence target.
For more smart trainer tips and tricks, please be sure to read All About ERG Mode