Gravel bike vs road bike: What’s the difference?
In the last few years, gravel bikes acquired an increasing attention on the global cycling landscape. The term “gravel bike” is, at first glance, seemingly self-explanatory: it is a bike designed to be ridden on unpaved terrain that often happens to be gravel. Yet that description still leaves much to be understood about gravel bikes, especially when most gravel bikes look very similar to their older cousins: road bikes. So, what exactly are the key differences between gravel bikes and road bikes?
Much of the core ethos of gravel riding is about exploration, adventure and epic rides where road conditions can be unknown. This means that a gravel bike has to combine the efficiency of a road bike, while still not being afraid to hold the course when smooth tarmac turns into dirt.
Frame design, geometry and riding position
To the untrained eye, most gravel bikes look exactly like their road brethren. A quick look at the geometry chart of a gravel bike will reveal a more upright riding position (similar to many modern endurance road bikes), longer wheelbase and a slacker head angle. This kind of geometry offers a more stable ride on rough terrain, as well as a boost in comfort on longer rides.
Early gravel bikes inherited gearing configurations from their road bike DNA. As gravel riding became more popular, the need for wider gearing became obvious as riders took their bikes on steeper and more technical terrain. Many of today’s gravel bike gearing choices are similar to modern mountain bikes, with single chainrings to and wide-range cassettes. There are riders who still want the ability to retain top end speeds on paved roads, in which case they opt for a more traditional double chainring setup. Some component manufacturers offer both single and double chainring gravel groupsets (e.g. Shimano GRX), while others decided to stick to single chainring for gravel (like Campagnolo’s Ekar groupset).
It could be argued that clearance for larger tires is the single most important difference between road and gravel bikes. Today, even 32C tires, which can be deemed “too wide” by road riding traditionalists, are considered too skinny by many hardcore gravel enthusiasts. It is now common to see manufacturers fitting their gravel bike offerings with tires approaching mountain bike tire width territory (e.g. 3T’s Exploro RaceMax comes with 650b x 61mm tires as standard). The science on this is clear: larger volume tires offer better traction as the terrain gets rougher.
Aside from gearing choices, gravel bikes retain componentry based on their road bike heritage, but that are adapted to their multi-terrain intentions. Their cockpits are fitted with shorter stems, and have wider handlebars with shallower drops that flare outwards to improve off-road handling. They borrow heavily from their other cousins: mountain bikes, with many gravel bikes now being fitted with dropper posts and even suspension forks (see the Cannondale Topstone).
If you only have to pick one, which would you choose?
The versatility of gravel bikes allows us to go farther on varied terrain. Will a road bike be faster? All other things being equal, on smooth tarmac a road bike will probably be faster, being optimized for the single purpose of road riding, aerodynamic efficiency and pared down lightweight components. That said, gravel bikes have the advantage of being able to keep going where the smooth road surface ends, and in doing so they open up riding possibilities that aren't always available with purpose-built road machines. Unless you are a pro getting paid to ride, more riding possibilities without having to worry about equipment choice is always good, and that’s where gravel bikes excel.