Many riders want to compare endurance bikes and road bikes and learn all the differences and matches between them.
The interesting aspect of the comparison is the speed deficit, endurance bikes are theoretically a bit slower than road bikes, but is it big or just a marginal gain?
In order to answer this question at least theoretically.
We have to calculate the difference in all points related to speed between the two bikes, such as aerodynamic weight, tire rolling resistance.
In this article, we will talk about the difference in speed in detail and answering the question of how much slower are endurance bikes compared to road bikes?
Endurance bikes are 2.5% slower than road bikes on flat roads, on a 5% grade climb endurance bikes are slower by 2.7%, when the speed increases over 40kmh the endurance bike can be 5.25% slower. This means that the difference is in aerodynamics.
In order to know the speed difference between endurance and road bikes, first, we need to know what affects bike speed while cycling or in other words resisting forces.
Resisting forces while riding a bike are:
- Tire rolling resistance.
Every power out from pedal strokes gets resisted by these forces, a formula that combines power, resistance forces, and speed is like the following.
Power = Fresist * Speed
Note: Fresist stands for the sum of resisting forces.
For more details about the calculation of this equation check this reference.
What is important for us in this equation is the speed, and it can be reformatted like this:
Speed = Power / Fresist
If we give the same power output from one rider for both bikes (road & endurance) the only factor the rest of us on this equation is the resisting forces.
Calculating the resisting forces for both bikes shows us the difference in speed.
For more accuracy of the comparison, both road and endurance bike should be from the same level which is from the high-end level.
Gravity is related to weight, by weight we mean the total weight of both the bike and rider.
Note: Weight on super flat roads with 0% grade is null, the only condition weight plays its major resisting effect is when the grade kicks in.
Trying to find the average weight for both bikes from the same level
The average weight for high-end level endurance bikes is 8.9kg or 17.8lbs when the average weight for high-end level road bikes is 7.3kg or 14.6lbs
Remember like we said earlier gravity has no resisting effect on flat roads, we will use this force only when comparing uphill speed differences.
Very underrated factor but it’s everything in cycling!
Aerodynamic or drag is the biggest resistor for cyclists especially when speed exceeds a certain level, this is why pro cyclists have everything aero as much as possible.
Drag is mainly related to the cyclist’s position on the bike.
Endurance bikes are known for the less aggressive positions than roads.
It has a higher stack with other geometry tweaks to offer the rider a relaxed position, on the other side, it makes him less aero against the wind.
When we look at it from a physical point of view the drag is related to the frontal area of the cyclist which is measured in (m²) as the surface gets larger the resistance gets higher and higher.
|Bike Type||Front Area (m²)|
The above numbers are from a great study done about descending positions & aerodynamics.
For more details about endurance bike position and geometry take a look at this detailed article.
Up to now theoretically, it is obvious that endurance has less drag than road bikes which is the main turning point in this comparison.
Tire Rolling Resistance
Tire contact with the road while cycling creates resistance power it mainly depends on the tire itself and total weight.
It is obvious that both bikes use the same tires, which makes the total weight the only variable to look for in the equation.
We discuss the weight difference in the gravity chapter.
Putting Everything Together
For 70kg rider with 200 watts power output on a super flat road here are the speed results:
|Bike Type||Speed (kmh)||Speed (mph)|
On 5% grade.
|Bike Type||Speed (kmh)||Speed (mph)|
The major difference between endurance and road bikes is aerodynamic, due to the different positions of both bikes.
Theoretically, the difference can be called a marginal, but higher speed like a pro peloton the endurance bike can be significantly slower than the road.
Endurance bike can be faster enough for amateurs and more importantly less aggressive position than the road bike, which make the bike more comfortable and faster.