WHY IS WHEEL STIFFNESS IMPORTANT?

Minimizing power loss is critical for speed and efficiency. The more a wheel deforms under force, the more energy is wasted.

WHAT TYPES OF WHEEL STIFFNESS ARE TESTED?

Transmission stiffness determines how much torsional flex a complete wheel displays when load is applied. This simulates pedaling torque at the freehub. Lateral stiffness determines how much lateral flex a complete wheel shows when side load is applied. This simulates force generated when rocking the bike side to side, on a climb for example, or when going into a corner. Less torsional and lateral flex mean increased rider input and less energy wasted as well as added stability and control under cornering load.

HOW IS WHEEL STIFFNESS TESTED?

For transmission stiffness testing, the rear wheel is secured at the axle, the valve hole in the rim is fixed and torsional force is applied to the freehub. The more the hub rotates, or “winds up”, within the wheel torsionally, the less transmission stiffness the wheel has. For lateral stiffness, both the front and the rear wheel are locked at the axle and lateral force is applied to the rim. The more distance the rim moves laterally, the less lateral stiffness it has.

STIFFNESS COMPARISON

STIFFNESS TYPECADEX 36 DISCROVAL ALPINIST CLXBONTRAGER AEOLUS RSL 37ZIPP FIRECREST 303 TL
Transmission Stiffness (N/mm) – Rear Wheel90.7451.1751.7250.78
Lateral Stiffness (N/mm) – Average of Front and Rear Wheel53.5333.0736.3034.46
Transmission Stiffness Difference (N/mm)*-43.6%-43.0%-44.0%
Lateral Stiffness Difference (N/mm)*-38.2%-32.2%-35.6%

* : These two lines show the difference of transmission and lateral stiffness between competitors wheels and CADEX 36 Disc. For example, -43% means 43 percent less stiff.

WEIGHT COMPARISON

WeightCADEX 36 DISCROVAL ALPINIST CLXBONTRAGER AEOLUS RSL 37ZIPP FIRECREST 303 TL
Wheelset1302g1248g1325g1352g
Weight Comparison-54g+23g+50g

WHAT IS STIFFNESS-TO-WEIGHT?

It’s easy to make a super-stiff wheel if weight isn’t a concern, but heavy wheels aren’t fast. For a wheel to be fast, it must be stiff and light. For this reason, producing a wheel with high transmission and lateral stiffness combined with low weight is the goal.

TRANSMISSION STIFFNESS-TO-WEIGHT COMPARISON

CADEX 36 DISCROVAL ALPINIST CLXBONTRAGER AEOLUS RSL 37ZIPP FIRECREST 303 TL
Transmission Stiffness (N/mm) – Rear wheel90.7451.1751.7250.78
Weight – Rear wheel721g686g725g739g
Transmission Stiffness-To-Weight Ratio0.1260.0750.0710.069
Transmission Stiffness-To-Weight Ratio Difference*-40.4%-43.6%-45.2%

*: This line shows the difference of transmission stiffness-to-weight ratio between the competitors’ wheels and the CADEX 36 Disc. For example, -40.4% means 40.4 percent less efficiency in terms of transmission stiffness to weight.

LATERAL STIFFNESS-TO-WEIGHT COMPARISON

CADEX 36 DISCROVAL ALPINIST CLXBONTRAGER AEOLUS RSL 37ZIPP FIRECREST 303 TL
Lateral Stiffness (N/mm) – Front wheel57.3132.2439.0435.25
Weight – Front wheel581g562g600g613g
Lateral Stiffness-To-Weight Ratio – Front Wheel0.100.060.070.06
Lateral Stiffness (N/mm) – Rear wheel49.7533.9133.5633.68
Weight – Rear wheel721g686g725g739g
Lateral Stiffness-To-Weight Ratio – Rear Wheel0.070.050.050.05
Lateral Stiffness-To-Weight Ratio – Wheelset Average0.0840.0530.0560.052
Lateral Stiffness-To-Weight Ratio Difference – Wheelset Average*-36.9%-33.3%-38.0%

*: This line shows the difference of lateral stiffness-to-weight ratio between the competitors’ wheels and the CADEX 36 Disc. For example, -38% means 38 percent less efficiency in terms of transmission stiffness to weight.

The Final Analysis

The CADEX 36 Disc offers better transmission and lateral stiffness over the competition. Combined with its light weight, the result is a best-in-class stiffness-to-weight ratio with real-world advantages in climbing, sprinting and descending.