Thank you to Liam Keatley for bringing this issue with the indoor cycling app to my attention! I love the discussions we have as an outdoor enthusiast community. I would be honored with your subscription. This is one difference between the Instinct 1 and 2 I have come across. The instinct 1 does not allow for gps (that I have been able to find) on the indoor biking activity unless you have an optional sensor. It is still useful as a way to categorize and record your activity though, and it is certainly better than nothing. Below is the official word from Garmin about the indoor biking gps tracking.

"When cycling with GPS turned off, speed and distance data are not available unless you have an optional sensor that sends speed and distance data to the device, such as a speed or cadence sensor." I do not have a problem with this except I do not have the option to turn gps on for this activity. Does anyone know if this is possible?

Stay tuned for a video on my own custom cardio activity that is set up for indoor cycling. Custom activities allow for gps tracking. Have fun out there and Semper Paratus!