enduro bearing testing machine with axial and radial load

April 17, 2023
BB Bearing Test Report comparing four Enduro BB bearings to models from six leading manufacturers
Read and/or download here


Soon after its founding, Enduro came to the realization that standard ABEC bearing industry testing does not adequately replicate bicycle bearing applications. Most bearing industry tests for bicycle-sized bearings are performed at very high RPM (between 5,000-10,000 RPM), and with only light loads applied in a radial direction. By contrast, bicycle hub bearings spin at just 200-300 RPM and bottom bracket bearings rarely exceed 120 RPM. Also not factored into standard ABEC industry testing are real-world cycling loads and stressors that subject headset, hub, bottom bracket, pivot and pedal bearings to much higher and uneven multi-directional, axial loads. Plus, there are harsh load spikes; a wheel hitting a pothole, slamming into boulders on steep downhills and landing jumps, or racing cyclocross through axle deep muck.

In order to simulate the real world forces and loads that Enduro designs our bearings to withstand ­– we built a custom test machine 20 years ago. In our lab, we test load forces as well as all manner of environmental wear-and-tear. For corrosion testing and to study the impacts of chemical goo on bearing performance and durability, we created secret sauce bearing baths that marinade bearings in everything from sea salt to gasoline to electrolyte drinks. 


Our recently refurbished machine, dubbed MaxTester, is currently abusing Enduro’s XD15 and our patent-pending Maxhit bottom bracket bearings to 3,000,000 cycles. In 2022, we begin measuring energy load (watts) and recently we added vibration sensors to the machine's long-standing ability to measure radial, thrust and axial loads (kilos); run speed (rpms), and run time (hours/minutes).

For more than two decades, we’ve subjected our bearings to every kind of abuse imaginable, then applied due diligence to develop appropriate test protocols for Enduro bearings as well as our competitors’ products. Our comparative analysis includes lab testing overlaid with extensive field testing and marketplace feedback. After many years and thousands of hours of data collection, we are confident Enduro’s testing protocols accurately measure bicycle bearing performance and durability.

Hub Bearing Test        

Using a 6902 radial hub bearing as the baseline, we tested Enduro’s offerings along with twenty other brands. To replicate real world use, each bearing was pressed into a 6061 aluminum jig serving as a surrogate bicycle wheel hub. Additional testing parameters included:

  • Multi-directional axial load forces combining 160 lbs. of radial force with 65 lbs. of thrust force applied to the outer bearing race against inner bearing race.
  • Speed: 120 RPM
  • Duration: 20 hours
  • Ambient temperature: 68º F / 20º C

After twenty hours of continuous load testing, all test subjects displayed minimal to noticeable deterioration. To determine the podium, we measured the galling pits on the surface of the inner bearing race. Here are results for the top four ceramic bearing performers in our 6902 radial hub bearing test.

 The 6902 Podium

  • 1st Place: Enduro XD15 Ceramic-Hybrid: 0.00 mm (that’s right, ZERO galling after 20 hours)
  • 2nd Place: Enduro Ceramic with ‘Zero’ treatment: 0.09 mm
  • 3rd Place: Leading Competitor A: 0.20 mm (twice as much galling as Enduro Zero Ceramic)
  • 4th Place: Leading Competitor B: 0.30 mm (three times as much galling as Enduro Zero Ceramic)

Twenty hours of testing *approximates* roughly two years of real world riding for an active rider or one year of pro rider abuse. The best 6902 bearing in our test showed no wear at all, the second place finisher showed negligible wear. Both spun ‘like new’ when installed in a wheel hub. 

The third place finisher, while showing 5-times the wear, remained serviceable when installed in a wheel hub.  The fourth place finisher, when installed in a wheel hub, exhibited tell-tale signs of aging. 

*Approximates: denotes variabilities such as weather conditions, terrain, rider sizes, riding styles and distances ridden.

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