In common, road bikes for sale come in three groups:
Road and Racing Bikes–As a general rule, road and racing bikes are built for speed and longer distances on paved surfaces. Thinner tires, lightweight 29-inch (700c) wheels and drop bars that allow for a more aerodynamic position are the norm. Most road bikes for sale, regardless of price, offer many gears for tackling both hilly and flat terrain.
Comfort/Cruiser Bikes–For tooling around on bike paths, light trails, or for cruising a quiet beach-side lane, comfort/cruiser bikes are the ticket. With a super-relaxed riding position, padded seats, and limited or no gearing, these road bikes for sale are made for enjoying the scenery and having fun with the family.
Mountain Bikes–With their larger tires, hill-friendly gearing and upright position, mountain bikes are very popular for all types of riding, both on pavement and off. Mountain bikes that are designed specifically for rugged trail use typically feature a suspension fork. Some may have rear suspension, as well. A quick change of the tires on any mountain bike–even one that you use regularly on trails–adds to its versatility and makes it a worthy street machine. from Amazon.com
2.Get the right size
Now you’ve decided which type of road bike you need, you’re going to have to look at road bikes for sale that are the right size.
In general a road bike frame’s “height” is generally thought to be ideal if it is 67 per cent of your inseam length.