Gravel races have become more commonplace across North America, with gravel bike technology subsequently being updated as well. At first glance, gravel bikes do resemble road or cyclocross bikes, but if you look a little closer, you will notice some key features that make them unique.
Below are some key differences you will find when researching the gravel bike vs road bike debate, along with the positives and negatives of both models.
The gravel bike frame generally allows for a large space for tires. The frames and forks make sure that a different tire size can be easily mounted and attached to the gravel bike. This can be a huge plus if you travel through an array of terrains while gravel riding and a frame with bigger tires will be able to make sure you are safer during a bumpier ride.
Also, gravel bikes generally have taller head tubes with head angles that allow for more versatile steering in adverse situations, i.e., making a sharp turn on a muggy gravel road. The wheelbases are also much shorter on road bikes, which means that they are typically less stable during the ride. The gravel bike’s long wheelbase optimizes comfort for long-distance off-roading.
Gravel bikes are really centered around providing comfort and efficiency for their riders. As such, road bikes tend to have a geometrical structure designed for racing that places the rider in a lower, arched position to maximize their aerodynamic speed.
On the other hand, gravel bikes have a longer wheelbase and a taller headtube that allows the rider to sit up in a more naturally comfortable upright position. Additionally, the headtube sits at a more relaxed angle that is slightly easier to control than the headtube on a road bike. This helps stabilize the rider when dealing with bumpier off-road surfaces.
As one would expect, based on the difference in expected terrain, gravel bikes and road bikes are made with a different tire size with variant tire pressure requirements.
Since road bikes are made for smooth flat terrain, they are designed to maximize speed with limited rolling resistance. This usually means that their tires will usually vary between 23-25mm thick with 90-100 PSI. This does make them faster on the road but will mean the rider will feel a jolt every time they hit some bump in the road or other rough terrain.
On the other hand, gravel bikes are designed with rougher terrain in mind and thus have gravel bike tires that are 30-40mm thick with about 40 PSI. The comparatively low PSI and thickness of these bigger tires help riders tread through bumpier terrain and are more efficient and comfortable for gravel surfaces.
While road bikes and gravel bikes may both have disk brakes, many road bike manufacturers still use the traditional rim brakes for their models. Disc brakes have been predominant in the mountain bike industry for many years but have only recently begun to be sparsely used with road bikes. This is because many peloton cyclists continue to prefer traditional rim brake systems because of their lighter weight.
On the other hand, gravel bikes are always enabled with disc brake systems. This is essential because gravel bikes have larger volume tires that a rim brake cannot really fit around. Disc brakes also emphasize optimal brake control and stopping power which is more reliable for gravel biking and a diverse range of terrain.
Gearing configurations on road bikes tend to be similar across the board. They usually have a double chainring with 39 or 52 teeth on the inner ring and 52 or 53 on the outer. Most cassettes are roughly 28-11 to 32-11 and have sturdy and reliable gears designed for flat surfaces and steep hills.
As for gravel bike gear systems, it is a bit more divided. The two major options are single-chainring and double-chainring gear systems. Shimano, one of the major cycle component manufacturers, produces gravel bike GRX group sets with both 1x and 2x gear systems.
Per your preference regarding the tightness of the range, 1x configurations will probably have an 11-42 or 11-40 cassette with a 40 or 42 tooth chainring. As for the 2x systems, there will usually be an 11-34 cassette paired with either a 48 or 31 tooth chainring.
One issue that will come up while changing gears with gravel bikes is chain slap from the rougher terrain. A chain slap is an annoying sound that comes from your chain hitting your swing arm on rougher hills. Single chainrings have a rotating tooth width that helps stabilize the chain on rougher surfaces, hence why many gravel bikes tend to prefer the 1x gear configuration.
Cockpit and Handlebars
Both road bikes and gravel bikes are designed with drop bars. However, gravel bike models rarely emphasize weight and aerodynamics to the same degree that road bike models do.
They tend to use aluminum for their handlebars and frame like hybrid or mountain bikes, which is a slightly heavier material. Gravel bikes’ drop bars also give the rider a wider grip with drop bars that curve outward which allows for more composure on rougher terrain.
On the other hand, road bikes usually use carbon fiber handlebars. Even though carbon fiber handlebars generally provide the rider with better damping and thus fewer vibrations during the ride, they also have less command on their turns because of flex. Aluminum handlebars on gravel bikes tend to have fewer problems with flex but do not have the same damping capabilities.
As we said above, gravel bikes have a wide array of tire sizes that can be attached and mounted for different types of terrain. This is not possible with road bikes, where you are generally stuck with the thin tire sizes designed for road riding on pavement.
Another way gravel bikes can be customized is through additional eyelets. Eyelets are tiny holes on gravel bikes where you can attach mudguards or racks. One drawback of road bikes is that you cannot customize them in the same way. Gravel bikes are very customizable to different terrain and weather conditions.
Can I Convert My Gravel Bike Into a Road Bike?
As all bike models become more and more versatile, many riders may wonder if they can refurbish their gravel bikes to function as road bikes.
Since gravel bikes have similar geometrical structures to those on road bikes, it is possible. However, the main problem would be the tire width and subsequent drag that limits ideal road speed. Even if road wheels were attached to a gravel bike, the original design was meant for different wheel sizes. Gravel bikes may not still be able to reach the same speeds as a normal road bike would.
The upgrade for road biking purposes gets even more complicated when we get to the issues with the upright handlebar positions and saddle positions. This requires some serious adjustment which may not be entirely feasible.
While it is possible that gravel bikes can come closer than hybrid or mountain bikes to mirroring the attributes of a road bike, they can never achieve the same optimal speeds that a mainstream road bike model can. Something for gravel riders to consider.
Which Bike Should I Buy?
Overall, the versatility of a road bike likely surpasses that of a road bike. There are so many ways you can customize your road bike to your liking and allow you to traverse different terrain. However, road bikes are incredibly useful for many riders, particularly for those who are biking novices.
If you plan to only bike on the pavement as many beginners do, then you likely have no use for the extra features that come with a gravel bike. Wider tires are unnecessary when riding on the road, and disc brakes, while useful, are not really needed unless you plan to ride on rougher terrain.
A gravel bike would be a better option for any sort of off-road activity and harsher weather conditions like strong wind or heavy rain. The added features on a gravel bike will make sure you are well equipped to handle those conditions in a way a road bike cannot.
Additionally, it should be said that gravel bikes will work fine on the road as well, just with slower optimal speeds.
Last Updated on July 19, 2021 by Matthew Carpenter