When leaning slightly to the right, the Neo disc touches the rotor, resulting in a loud metallic scraping sound. Sometimes, the disc itself will also cease movement.
Root Cause
This behavior is caused when the axle breaks free from the swage inside the Neo. The result is that the axle sags, and the slight sag is enough to cause the disc to hit the stator.
Additional Information
Historically, this condition would have been considered “fatal” to Neo units with this problem. For Neo and Neo 2 units, the answer to this problem is in the form of an axle reinforcement device for Tacx Neo trainers called “ReAxle”. It can be purchased online at reaxle.com. We have tested this device ourselves, and we have literally hundreds of testimonial reviews from folks all over the world who’ve used this device, not only to resolve issues with a broken axle, but also to resolve shuddering and other noise issues, and most significantly — install it ahead of time to prevent the axle from ever sagging in the first place.
For Neo 2T units, Tacx and Garmin have declined to make the axle assembly available as a spare part, and fixing the issue requires some specialized metallurgical know-how and equipment in terms of welding and turning. Otherwise, this condition for Neo 2T is still considered “fatal”. You will need to contact Garmin support and see what they will offer you in terms of replacement.
It is our recommendation that you always remember that you are using a stationary trainer, and you are responsible for ensuring that your upper body remains still to prevent damage to your bike frame, your trainer, and most importantly, yourself.