One in good working condition! Most riders will ride road bikes with drop-style curved handlebars, but touring or hybrid bikes with straight bars are just fine, too, as are recumbents and tandems. What’s most important is that you’re comfortable and that your bike will hold up through multiple days of riding.
If you are in the market for a bike, we encourage you to visit a bike shop in your area and explain that, during BikeMaine, the bike will be used for riding an average of 55 miles a day on tarred Maine roads (translation: expect the occasional potholes and cracks). No need to carry luggage (as baggage service is included in your registration), but the bike should be light enough that you can be comfortable climbing about 2000-2500 feet a day.
That being said you may look to rent a bike in the area and not worry about bringing (or shipping) your own bike with you and that is perfectly fine. You know your body and how you will adjust to a new bicycle better than we do!
PREPARE YOUR BIKE: If you are bringing your own bike, please please please have it inspected at your local bike shop. This will reduce the chances of having mechanical problems along the route. A tune-up is a must whether you do it yourself or have a mechanic do it for you. We (and the past BikeMaine bike mechanics) strongly encourage you to schedule a Professional Bike Tune-up and have your mechanic inspect the bike thoroughly, clean and re-grease all cable pinch bolts, saddle rail clamp and bolts, and the seat-post collar bolts, replacin worn out parts if necessary. If your shop has or can order your bike’s specific rear derailleur hanger, buy one as a spare and bring it with you. If you have any nontraditional wheel spokes that are integrated to the manufacturers hub and rims, it never hurts to have those on hand for the bike mechanics to install, if need be. We want you and your bike to ride the whole route!