Tesla’s recommended roof rack is made by Whispbar. Only Model S cars equipped with the Pano roof support this roof rack system. The rack system has additional attachments options for bikes, skis, a Kayak, or several cargo carriers.

• Rack for Model S at Tesla Motors
• Rack Attachments from Whispbar (bike, kayak, and cargo carrier)

For cars without the Pano roof, there are Sea Sucker Bike Racks  is one option for holding bikes.

For the Model X, consider using the Tesla tow hitch rack.