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Testlab Wheels & Rims

Testlab Wheels

Wheel Fatigue Test

The drum rig is used to simulate the forces exerted on the wheel when in motion. Depending on the wheel type, various tests are carried out by loading the wheel with different weights, introducing obstacles, varying the speed and increasing the number of impacts to reflect the specific type of use.

This does not include testing the wheel at an angle on the drum, which we feel represents an unrealistic application of force. Instead, we use a lateral force test, which we think is much more representative. In the lateral force test, we introduce bumps that hit the tyre tread laterally at the tyre contact point to send a lateral shock through the wheel, which is far more true to life.

Potential issues:
  • Hub flange breaks
  • Hub axle breaks
  • Spokes and/or nipples break prematurely
  • Rim tears, especially in the vicinity of the spoke holes
  • Cracks in the rim
  • Spokes coming loose


Number of drum rigs: 2

Brake Fatigue Test

We use this rig to simulate real-life braking processes on wheels fitted with disc brakes. As far as we know, there is no other test rig of its kind in the world – yet this kind of testing is vital. That's why we developed and built the rig ourselves to be able to test the huge forces that disc brakes exert on wheels. The brake rotor is affixed to the rig, which is compatible with all brake disc diameters and disc standards. Braking force is applied to the wheel using a belt whilst the force of the weight distribution created by the load change is applied from below using a cylinder. This cylinder applies the force via a floating plate at the precise moment that the braking force is applied to the wheel.

Thanks to this rig we have been able to double the durability of our hubs with a weight penalty of just 10 grammes. Potential issues:

  • Hub flange breaks
  • Spokes and/or nipples break prematurely
  • Rim tears, especially in the vicinity of the spoke holes
  • Cracks in the rim
  • Spokes come loose

Drive Fatigue Test

This rig realistically simulates the force transmitted to the wheels by the drivetrain. We developed it together with one of our suppliers and, as far as we know, only one other competitor is currently using a rig of this kind for similar testing. The wheel itself is mounted to a swing arm and held in place with a belt. Weight is added to the end of the swing arm to simulate the maximum vertical wheel force. A lever attached to the freewheel body applies a given torque (chain load). This allows us to test the durability of the entire rear hub, the spokes and the rim.

Rim Impact Test

This test rig simulates how rims or full wheels behave in the event of an impact.

The rim is affixed at two defined points in a way that allows it to deflect downwards and laterally. The impact hits the rim at a realistic 20°.

Potential issues:
  • Dents in the rim flange
  • Deformation of the rim profile
  • Crack in the rim

The test can be performed with or without tyres.

Spoke Pull Out Test

Using this rig we can test the force that a rim is able to withstand in the area of the spoke hole. As this is one of the most critical areas of the rim, we use this test both in our development processes and in quality control.

Potential issues:
  • Spoke hole buckles
  • Spoke hole tears away
  • Rim profile is deformed
  • Rim breaks

Wheel Stiffness Testing

Wheel Stiffness Test (horizontal):
This test measures the lateral stiffness of our wheels. A wheel is clamped horizontally in the rig and increasing force is applied up to a known limit. The amount of deflection is measured and recorded continually whilst the force is being applied. This gives us undistorted and completely objective information on the influence of spoke tension, spoke dimensions, rim material, rim profile, spoke lacing type and hub type on lateral stiffness. The test can be performed with or without tyres.

Wheel Stiffness Test (vertical):
This test measures the vertical stiffness of wheels. The wheel is clamped vertically in the rig and increasing force is applied up to a known limit. The amount of deflection is measured and recorded continually whilst the force is being applied. The test can be performed with or without tyres.

Wheel Overload Test:
This tests the amount of force that is needed to cause the wheel to collapse (cave in on itself). A wheel is clamped in the rig and increasing force is applied until the wheel crumples. We feel that this test is absolutely essential in order to rule out any failure of this kind when out on the road, especially when it comes to lightweight carbon wheels. The test can be performed with or without tyres.