CycleOps Science: Resistance Curves

CycleOps Science: Resistance Curves

Ever wonder how our CycleOps indoor bike trainers work? What makes them unique over other brands like Kurt Kinetic, Tacxor Wahoo Fitness? Easy. It all comes down to science – and PowerTuned technology.

This week we're taking a closer look at resistance curves and what makes ours so special.

Lesson 3: Resistance Curves and PowerTuned Technology

Indoor trainers are made of two parts: physical elements and mathematical elements – and when it comes to resistance curves it is all about math. We use wheel speed, PowerTuned Technology and cadence to create four distinct resistance curves: linear, adjustable, progressive and controlled.

While each of the three factors is needed to calculate our resistance curves, PowerTuned Technology is unique to our trainers thanks to PowerTap technology. Creating resistance curves with PowerTuned Technology allows us to produce the widest range of resistance at real world speeds by matching the rider with the right flywheel and resistance unit. When the optimal flywheel mass to resistance type is found, real world inertia is achieved and no unnecessary weight is added to the trainer. It's a win-win all around.

Using PowerTuned technology and the PowerTap powermeter we can graph the amount of power it would take for an average rider to maintain a specific speed while on the bike trainer. Take a look at our resistance curves below. Each graph depicts speed horizontally on the x-axis versus power vertically on the y-axis:


How it works: when you pedal faster or shift gears, the resistance changes proportionately to your adjusted speed. We have trainers that are straight-up linear or those that can be adjusted. Compared to the other resistance curves, this feels the least like riding outside.

Mag Trainer Resistance Curve


How it works: the faster you pedal or shift gears, the higher the resistance – just like when you ride outside. For example, it is twice as difficult to ride at 20 miles per hour as it was at 10 miles per hour. If you close your eyes, you could almost swear you're riding outside on the open road.

Wind Trainer Resistance Curve
Fluid Trainer Resistance Curve
Magneto Trainer Resistance Curve
SuperMagneto Trainer Resistance Curve
JetFluid Trainer Resistance Curve


How it works: resistance is controlled by a head unit, like the PowerTap Joule GPS, or better yet – CycleOps VirtualTraining. The trainer adjusts while you pedal and you cannot get any more true-to-the-road feel than this.

Powerbeam Trainer Resistance Curve

So where did these resistance curves come from? Renowned scientist Dr. Allen Lim worked with professional cyclists to develop a power curve based on a hybrid of road and time trial positions, finding the point at which a speed of 25 mph overlaps with an output of 400 watts.

CycleOps turbo trainers that feature PowerTuned Technology have a better road feel, are more realistic overall and optimize training.

Want to learn more? Take a look at our full line of indoor trainers. And if you're ready to bring your inside ride to life, add in our CycleOps VirtualTraining software.