In-house marketing is great. Get teaser flyers and banners up before the bikes arrive. Ask your dealer if their company offers a promotional video, and, if so, have it playing at the front desk.
Then, after the bikes arrive, don’t let anyone on them except the instructors for the first week. Have the instructors work out together during prime time to build the members’ interest.
Find out if there is a cycling club in your area. This is a great place to make contact with cyclists who may want to teach. It’s also a great place to find cycling enthusiasts; these people will love this program.