Cannondale invented the BB30 system back in 2000, consisting of two main components: an oversized 30-millimeter crank spindle and a specifically designed, and also oversized, bottom-bracket shell. Despite early BB30 generally being a pile of horse crap, Cannondale at least took into consideration that a larger-diameter spindle required a larger-diameter shell to account for bearings—which, you know, are kind of important.
Many say that BB30 was a horrible invention that should have never made it beyond a racing prototype and should not have thrown the entire bottom-bracket game into upheaval. But that's what happened anyway, and it wasn't long before people forgot that bearings were an integral part of the interface between crank and frame.
By "people," I'm mostly talking about Race Face (they aren't the only culprit, but definitely the largest). Race Face utilized 30-millimeter spindles for its Cinch series cranks and made a 'bottom bracket' for them to fit into BB92 shells—which of course are specifically designed around 24-millimeter spindles. The resulting system, if you could even call it that, serves little more function beyond parking lot test rides, but somehow wound up as original equipment on a zillion bikes around the world. If it sounds like I'm being a bit harsh here, it's only because countless people have spent tons of cash on new bikes only to discover they've been shanghaied with opposing standards and a band-aid bottom bracket.
This brings us to the pile of bearings and grease you see here. The good folks at Enduro Bearings developed what has proven to be a remarkably good solution to this reckless act of standards swapping. If you're one of the thousands of poor souls stuck in the aforementioned situation, or you're just a weight weenie like longtime friend of Bike, Carl Bauer, who's just gotta have that aluminum spindle, then this is the pile of bearings and grease you've needed.
Carl put a whopping 5,000 miles on the Enduro bottom bracket before the bearings developed enough play to render it officially beat down. Enduro managed to make a robust system in such a tight space by going wide with dual-row 440c stainless steel bearings on each side. Stainless steel provides far better corrosion resistance in places that are likely to get wet, like bottom brackets. Besides the bearings, the kit is pretty simple, containing some plastic spindle spacers and a set of seals.
Carl managed to get muck past the seals and into the bearings a few times but was able to revive them by removing the seals, cleaning the bearings and repacking them with fresh marine grease. Stainless steel is a little softer than the chromium steel Enduro uses in most of its bearings. The bearings won't rust easily, but it's best to service them any time they start feeling gritty to ensure you'll get as many miles out of them as Carl did.
It's pretty tough not to be impressed with a set of bearings that lasted 5,000 miles, through a wet winter, in two separate frames. These little bearings outlasted two sets of Next SL cranks—did we mention that Carl is a punisher? With those stats, suffice to say that this isn't a band-aid, it's a real solution.