Override hr from external device

Ive been using my 970 connected to a spin bike at my gym through ANT+ however, the bike does not have a hr monitor and needs an external one to be connected to it (which I dont have). As a result during activities it shows my HR as 0 the entire activity. Is there a way to use the forerunners hr during the activity and get all the cycling data from the bike?

I've gone through the accessory settings on the watch and I can only adjust specific settings around the wheels and other things, nothing related to heart rate.