smashndash

Uh.... wasn’t Jobst Brandt the one who thought spokes act like pillars in compression when under load? And wrote a book saying that? He said that the wheel load was carried by the bottom few spokes. I’m 99.9% sure that’s a load of bull because there exist spokes that are literally string. Considering that wheel science was what he was most known for, I would say no, not everything he did stood up to critical review.

As to what Hambini says, I am a big fan, but I take what he says with a grain of salt. Angular contact bearings may be slower when riding completely upright (as we usually do), but when throwing the bike around or cornering, I have yet to see a proper comparison. Faster also is not inherently the same thing as longer-wearing, just as quieter is not inherently the same thing as faster. Chris King, Shimano, Campy and Wheels mfg all cling to cup and cone bearings. We can’t assume they’re all morons. They just have priorities beyond straight line speed.

As to BBInfinite’s claim of “industrial bearings are not inherently better” - that’s true. Of course, it’s better to have a bearing that is more suited to your task assuming everything else is equal. But everything else is not equal. The precision to which a bearing is machined can seriously affect the drag and longevity. Hambini has posted a comparison (somewhere). It shows that, under simulated bike conditions (in terms of speed and weight), NTN bearings last the longest. And that is going to matter a lot more to people than a tenth of a watt. The gains one gets from properly aligning the bearings will far exceed any gains from bearing choice within a reasonable range. It’s arguable that Hambini has done the most to bring this issue to the public eye than anyone else. Even BBInfinite.

Hambini says spin-down tests are a poor indicator of drag and I disagree with him. It’s a poor indicator of how drag scales with load, but I think it does a fine job of showing the amount of “base” drag caused by seals, grease and misalignment. I have a Hambini racing BB. It doesn’t seem to spin quite long as BBinfinite BBs do in videos. I can imagine it’s because of the excessive, inappropriate grease. But it’s still really, really good, and there’s some of evidence to suggest than NTN bearings stay faster for longer than many bearings.

Since BBInfinite is claiming that their bearings that they’ve made are so much better than those made by multi-billion dollar corporations that specialize in bearings, the onus is on them to compare their steel bearings to NTN/SKF/FA G etc. I know ceramic is faster initially, but I think, for the cost, we would need to see some hard evidence that they last at least as long as steel (because in theory they should not).

It’s interesting to note that Hambini Racing BBs use “contactless” seals and BBinfinite bearings use “mid contact” seals, but still seem to have less base drag. Or do they? Who knows. EDIT: Also it’s worth noting that most NTN bearings normal people can buy online are P0 or P6 whereas BBInfinite claims to be Abec-7 aka P4. So BBInfinite may actually be better than NTN.