Enduro debuts ultra-durable Solid Lube bearings for BBs, hubs, and pivots
Back at the 2019 Eurobike trade show (remember when trade shows were still happening?), Cane Creek introduced a bottom bracket that was built with special bearings developed by SKF. Instead of being filled with conventional grease, the cartridges were packed with a novel oil-infused solid polymer that was supposedly completely maintenance-free and self-lubricating. Even earlier than that, CeramicSpeed showcased something similar with its SLT bearings, although it’s unclear if that ever came to fruition.
Either way, it seems there might actually be something to those claims, as Enduro has now unveiled a solid-lubricant bearing design of its own.
Enduro’s new bearing — simply called Solid Lube — starts out as a conventional cartridge with bearing balls held inside a steel retainer ring and the same 52100 chromium steel races that Enduro uses in its other ABEC 5 bearings. But instead of using typical grease, a special “foamed polymer” is then injection molded into the cartridge interior, filling the entire cavity. Like the SKF bearing, that polymer is then infused with oil so the bearing is essentially self-lubricating.
“While a nylon cage is possible, a steel cage is preferable to hold more of the polymer and more completely cover the balls,” explained Enduro owner Matt Harvey. “We have been working on getting the right formula off and on for 15 years. Some solid lubricants are very stiff and grip the balls so tightly that they skid and feel rough. Other solid lubricants that run smoother are brittle or soft, and can self-destruct or break apart. We have found a balance in our formula that has a waxy smooth run, but [is] robust and tough at the same time.”
The porous nature of Enduro’s polymer and that infusion of oil are obviously what provides the self-lubricating capability. However, Harvey says that the very close fit of all the components is also one of the key elements to the bearing’s claimed durability. Even if dirt or water gets past the conventional outer seals, there supposedly isn’t enough room for any of that stuff to stay inside.
“At 20 hours [on our test machine], you begin to get some wear on the races on our standard bearings,” explained Enduro owner Matt Harvey. “In some cases for bearings we test against, they have catastrophically failed at 12 hours, or are severely worn at 18-20 hours. For the Solid Lube bearings, the races were still smooth and as-new feeling. We do not get any significant wear with the Solid Lube until about 40-50 hours.
“We then ran the same tests with salt spray and an acid. This normally cuts in half the time the bearings will survive as it promotes early galling. Surprisingly, the salt and acid combos did not change the results.”
Harvey says that Enduro has had a variety of “top gravel, ‘cross, and road riders” testing its new bearings as well (he couldn’t name them due to sponsor conflicts), and so far, “the bearings are holding up in the same manner as the lab testing I mention above. We did test them also without seals while power washing them after every ride. In this case, you can eventually drive the oil out of the solid lube. We won’t recommend doing this, but it seems the easy solution is just to add some new light oil of which you can use several types — or [DuPont] Krytox if you want to get fancy.”
Just bottom brackets for now, but more applications on the way
Enduro is launching its new Solid Lube cartridges only in its TorqTite thread-together press-fit bottom brackets for now, which makes sense given that they’re arguably the hardest-working — and most failure-prone — bearings on your bike. In a sign of confidence in its new bearing design, Enduro is backing those Solid Lube bottom brackets with a two-year warranty that has no maintenance requirements attached.
The new bottom brackets also feature a more simplified two-piece construction in place of the original three-piece design, with a smaller-diameter center section that leaves more room for internally routed hoses and housings.
The retail price isn’t bad, either, at US$129 / AU$166 / £94 / €109, and production units should be arriving at online and brick-and-mortar retailers any day now.
As you’d expect, Enduro has other applications pending.
“We will eventually be offering MAX-type bearings for suspension pivots with Solid Lube, with no maintenance and the same warranty,” Harvey said. “Eventually, ABEC 5 bearings for hubs will also have this option. With the promise of no maintenance for considerable periods of time measured in years, these bearings approach some of the same performance features of XD-15 bearings, but at a fraction of the price.”
One of the most promising applications may be be headsets. Enduro already makes headset bearings and complete headsets, after all, and the increasing popularity of road bikes with fully internal routing is now placing a higher priority on headset bearing longevity given that once-simple replacements now require you to disconnect most (if not all) of the derailleur and brake lines.
But unfortunately, Solid Lube headset bearings may be a little further out than some of us would like.
“At this point we cannot make Solid Lube angular contact bearings,” Harvey said. “We cannot use a steel retainer for angular contact bearings because of the assembly procedure and the restricted room inside. When the Solid Lube is injected, you cannot guarantee a complete fill around the nylon and get enough material in that it holds together properly. We are able to make MAX-type bearings [where the races are filled almost completely with bearing balls without a retainer for a higher load rating, but also more friction – Ed.], but we have to make a special ball separator for each size that is removed before injection. Sometimes from the force of the injection, the balls will move slightly and they are not perfectly spaced every time, but not a big concern in testing for the MAX bearings. Molding the solid lube without a retainer in an angular contact bearing is something we are looking at, but we are not there yet where we can guarantee even ball spacing.”
Nevertheless, we’ll be watching this one closely for sure.
More information can be found at www.endurobearings.com.