I've been wanting to keep track of my Airdyne workouts for quite awhile. I bought a cheap one off Craigslist for 50 bucks and the old computer never worked. I installed a Sigma 509. Thanks to Joe owner of Crossfit 8th day here in Grand Rapids, MI for helping me out. Don't poo poo the power of the Airdyne. You can get a tremendous and safe workout on one.
Here is how the actual set up of the bike computer can be done