Bottom Bracket Selection Guide
The Magic Bearing!
Years ago we saw the proliferation of 30mm spindle cranks and the widespread adoption of BB86 and BB92 brew into a perfect storm of hapless customers afflicted with epic levels of creaking from bottom brackets that lasted about a minute. The problem stemmed from BB86/BB92’s restrictive 41mm diameter, a full millimeter smaller than the 42mm outer diameter of a 6806 bearing, the very bearing one needed to run a 30mm crank set. And so, the bearing that was needed was too big to fit in the space provided.
It’s no surprise that Shimano developed the Shimano BB86/BB92 standard to effectively block the use of everything but their own 24mm crank systems, Gxp, and Shimano crank clones like MegaExo that are rarely used. Shimano is run by a savvy lot for sure, but they don’t seem to understand a cyclist’s mentality very well at times. We don’t like to be forced into choices. That’s not choosing. I’m sure the first time an American saw that tiny hole in their bike their immediate thought was, “How big a thing can I stick in there and won’t that be fantastic”. Enter, the solution: The 4030 bicycle bearing.
Measuring 30mm x 40mm x 7mm, the 4030 bicycle bearing falls right in between the larger 6806 “BB30” (30mm x 42mm x 7mm) bearings and the much smaller 6805 (25mm x 37mm x 7mm) bearings used on a typical Shimano or Gxp set up.
We get questions about 4030 durability because the bearing is smaller than a 6806, but the fact is that the 4030 has only one less ball than the 6806, and two more balls than the 6805, with plenty of race thickness to boot. Therefore the 4030 bicycle bearing is just as durable as any other bearing we sell.
We use the 4030 bicycle bearing in our BB86-30mm and Dub, BB92-30mm and Dub, BB30/BB30A-30mm, and our English/Italian threaded BB’s for 30mm and Dub.
4030 equipped bb’s are backed by our LifeTime Bearing Exchange Warranty for all Ceramitechs and WS2 coated Ceramitechs and our 1-year Bearing Exchange Warranty on all ABEC-7’s.
How the 4030 bicycle bearing came about:
About five years ago we were asked by Scott Warren of Orbea fame to come up with a BB to run the relatively new-at-the-time FSA BB386Evo crank in the BB86 Orcas his pro continental women’s team was set to race that season. Our first question was “Why do that when you can run an FSA MegaExo in a BB86 Shimano BB and be done with it”. But racing is about winning AND sponsorship, so it doesn’t work like that. The team was being sponsored by FSA and FSA was pushing the 30mm Evo hard, so it had to be Evo cranks in the Orcas or nothing.
We used a single, and then double row 6706 (30x37x4) arrangement because that was the only bearing available at that time to journal a 30mm spindle yet with an OD smaller than 41mm. By doubling up the result was a relatively robust system that spun like absolute mad, but durability was a huge problem and failures tended to be catastrophic. Although we were getting emails from all over the world requesting---practically begging---us for a bb to fit a 30mm in BB86/BB92 that performed and lasted, we scrapped the 6706-based BB project and quickly moved in another direction: We needed a custom bearings size.
Wes, BBInfinite’s engineer and co-founder, drew up a print for the revolutionary 4030 bicycle bearing and, after nearly two years of development with bearing manufacturers, we rolled it out.
In the coming years you will see the 4030 bicycle bearing everywhere because it’s necessary, because it’s the perfect no-compromises solution, and because cyclists want what they want, and we want them to have it…and unfortunately we couldn’t patent it:)
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