On a reasonably flat commute you can average about 16km/h on a road bike. However, a road bike’s speed can go as high as 30km/h or even 35km/h for the professional cyclist or a person who is reasonably fit. Overall, you will be about 15-20% faster on the road bike with the same effort as compared to when you are riding a mountain bike with its knobby wide tires and flat handlebars.
Nonetheless, while the road bike is usually faster than the mountain bike, you can make a mountain bike faster by doing the following.
- Change out the wide knobby tires for thinner high pressure tires. There are tires that run at between 75-90 lbs of pressure and are between 1.25″ and 1.5″ inches thick which will significantly reduce rolling resistance.
- Set the suspension on your mountain bike as stiff as it can be or if you can lock it off. This will result in more of the effort from the pedals being transferred into the drive train rather than being lost to shock absorption.
- Get Clipless Pedals – Clipless pedals usually offer better speeds from the more efficient pedal strokes.
Differences Between the Mountain Bike and the Road Bike
There are all manner of bike types for every possible terrain you could think of. Trails and pavement tend to have very different characteristics which is why a very specialized bike is needed for these types of terrain. The mountain bike is a bike that was designed much later than the road bike and comes in different builds and styles designed for riding on rough terrain. On the other hand, the road bike is made for pavement riding rather than off-roading or rough terrain. It is one of the earliest bikes to be made and is more than 100 years of history and most other bike types are descended from it.
Road bikes typically have higher gears than mountain bikes but they also have a higher high gear. As such even though the mountain bike provides more power, the road bike will usually have greater speed. This usually comes form the design of the rear cassette and the front derailleurs.
- Rear Cassette – The road bike usually has a smaller rear cassette as compared to the mountain bike. Only touring bikes have large cassettes. The road bike typically has more hub splinging and individual gears to enable the bike cope with greater forces. With several gear groups the forces applied on the carrier are distributed more evenly.
- Front Derailleurs – Modern road bikes typically come with three chain rings as compared to the two on a mountain bike. Since the road bike comes with more chain rings, it can attain greater speed by shifting into a heavier gear.
Road bikes are designed with thin high pressure and smooth tires which makes for greater acceleration given that there is not much friction between the road and the tire. Mountain bikes usually have heavy, wide, thick, soft and knobby tires which decrease the speed of the bike as it is more susceptible to air and rolling resistance.
Road bikes are some of the lightest bikes you could ever buy with their tubular and thin components. This makes them very good at accelerating as they are not weighed down by their component. Mountain bikes tend to have thick tubular frames and forks, thick tires and wheels all of which increase the weight of the bike and slow down the bike.
The drop bars on a road bike call for a hunched forward aerodynamic position which reduces drag and wind resistance making the bike accelerate faster. This is as compared to the flat bar handlebars on a mountain bike that call for a rider to sit upward which increases resistance and slows down the rider.
Mountain bikes usually come with suspension due to the fact that one will be riding in rough terrain. However, the suspension usually absorbs pedaling energy some of which is list in the springs of the suspension. Road bikes do not have suspension systems and exchange more power and acceleration for a bumpier ride.
Road Bike vs Mountain Bike for Exercise
The workout goals and plans is what will determine which bike is best for you. If you intend to workout for cardio then a road bike which provides great efficiency is preferable. Since it does not take too much effort, you can perform sustained cardio exercises on a road bike without getting too tired fast.
Moreover, the lightweight frames and overall design of road bikes means you can ride for long distances to develop endurance. This means that one can get an all around inclusive workout on the road bike.
If you are looking to lose weight and get fit. the mountain bike may be your best bet. Their robust and sturdy frames hold much weight while the flat handlebars mean one can ride in a posture that strengthens core muscles.
Riding in a straight posture also builds muscles particularly on the legs and this will make it easier to burn more fat and calories even over short distances. You will also need to expend more effort and energy given the weight of the bike and the fact that it is not as streamlined as the road bike.
Overall, road bikes are excellent if you need an overall body workout and cardio while mountain bikes are great for muscle building and building endurance. The choice that will be made will usually depend on the fitness goals you have.
Mountain Bike vs Road Bike Effort
Using the model on Bike Calculator, 58 watts of power would be required on a mountain bike while 34 watts would be needed for pedaling 15mph. That is approximately 60% more effort needed while riding a mountain bike. However the gap lessens with increasing speed. By the time you are pedaling at 45mph the road bike would need 589 watts while the road bike would require 517 watts which is a difference of only 12% between the road and mountain bike.
However, it is important to note that while the road bike does need less power on flat surfaces, you also have to take into account other aspects. Some of these aspects include: the obstacles on the trail, the aerodynamics and resistance, and the surface on which the bikes are ridden.
Mountain bike power vs Road Bike Power Experiment
To illustrate the difference in effort between the mountain and road bike Jason Hilimire used a PowerTap power meter on two 10 minute climbs. The graph below shows that there are more fluctuations on the power meter during the mountain bike climb.
On the mountain bike, Hilimire averaged 220 watts and 246 watts on the road bike. However since rode the mountain bike off-road, there was much more effort that topped and surpassed the 300 watt mar while the road bike rarely hit 300 watts. From the data set it is evident that more than 300 watts of effort that lasted between 5 and 25 seconds were needed for the mountain bike.
When riding a mountain bike, these short bursts of effort are common. Riding a mountain bike, one would need to have these bursts of effort and power due to the switchbacks, rocks, short steep climbs, ruts and roots among many other obstacles. When riding a mountain bike one has to produce such effort to maintain speed and clear the highly challenging terrain.
On fairly technical terrain the wattage can got to zero and pedaling on a mountain bike can come to a stop and then immediately go from 0 to 300 as shown in the graph. It is these changes in wattage and short bursts of effort that make road biking very different from mountain bike racing.
Why Road Biking is Better than Mountain Biking
Everyone has seen that group of serious looking cyclists ride silently byhunched over skinny wheeled bikes. Road race bikers love to wear elastic skin tight garments and often joust with mountain bikers on who has the best world. While cycling on whatever bike comes with a lot of benefits, there are several benefits to road biking that riding a mountain bike does not provide. Some of these include:
Not everyone lives near a mountain bike trail and this can make mountain biking almost impossible in the city. While you can always hop into the car or train to go find a trail that can become expensive or impractical. However, paved roads are all over the place and you can get your riding fix almost anywhere you live with a road bike.
It is Great for Fitness
There is no better bike for getting a great cardio than a road bike as they are fast and require less energy which means you can ride for hour building endurance. Moreover when road riding you can train specific aerobic systems for a great workout as opposed to mountain biking where riding for endurance is almost impossible due to the short bursts of energy and effort required.
Maintenance is Easier
Mountain biking is great for going off-road and hitting the trails in all manner of weather. However all that mud and grit can be hard on the bike. You will often have to maintain and clean the bike before storing it. With a road bike there is not much cleaning required and the bike does not take much of a beating which means you do not have to spend so much money maintaining the bike.
Mountain bikers typically average 10mph on single track riding. On uphill riding the mountain bike will average 8mph and 12mph on downhill sections. Taking the two together the average speed is 17mph which can go up to 30mph when riding the bike downhill
Mountain bikes are made to be ridden both off-road and on-road unlike road bikes which are best ridden on pavement and will usually not be built strong enough to handle the rigors of riding on trails and tough terrain. Mountain bikes while slower and less aerodynamic can be ridden on the road just fine.