brendon_ak

win

das_pyrate

are dura ace hubs really loose bearing? why?


also wtf dura ace doesn't belong on a leader

brendon_ak

Loose bearing hubs are smoother and can spin faster

Oh, once you see my leader you'll take that back...

das_pyrate

i disagree on both, but i'd still like to see it.

brendon_ak

You can disagree all you want with regards to the loose bearing, but science and research will prove you wrong.

Any high end hub is built with loose bearings, ever wonder why?

As for the frame, I'm looking at it right now, and boy it is hot.....

mihlbach

DuraAce hubs are loose bearing because of NJS rules. There is no other reason. You can convince yourself that they make you faster, but that is total nonsense. Seal drag from a good set of sealed bearings is so exceedingly minor, it doesn't even matter to pros.

Furthermore, the idea of wanting looseball hubs specifically for the purpose of riding in bad weather is asinine. The bearings roll against the inside of the hubshell. Contamination will eventually result in pitting of the hubshell and diminish the performance of the hub, ultimately rendering it useless.

Cartridge bearings are not only resistant to contamination, but the moving surfaces are contained within the bearing cartridge which is pressed into the hub. No matter how dirty the bearings get, it will not damage the hub.

the_don

Sealed cartridge bearing hubs and swap them out for completely ceramic bearings FTMFW!!!

octopus magic

My 2009 Zipp 900 disc has cartridge bearings. I'd consider it a pretty high end wheel, personally.

Ceramic bearings on bikes is dumb and a waste. Ceramic bearings were initially designed for extremely high rpm rotations (like a turbocharger on a car which will reach upwards of 18k rpm).

Considering most of us can max out at like, 200ish rpm, it's a bit silly when that's more than in specs for a good cartridge bearing.

bones_mcbones

I especially like how the jackass who made this mispelled "skis". No apostrophe necessary.

the_don

More glaring is the invisible!

ValVal

+1
https://www.businesscycles.com/thub-formula.htm

das_pyrate

entirely incorrect. i'd like to see the science and research that will prove me wrong.

barely ANY high end hubs are built with loose bearings, because it's a step DOWN from sealed.

ps a hawt looking frame ≠ a good quality frame

Tomo_Ishi

Loose balls can be packed so they are as good or better than sealed bearings. But I think the problem is how big the balls and how well you pack em. (Or how much you wanna fiddle with em)

I think bigger balls are gonna be nicer in swimming through grease than small balls. But the balls gonna be more stressed out because fewer balls can fit in. Catch-22 huh?

And, I heard the rumor where racers prefer (loose-balls) hubs packed with least amount of grease as safely possible because grease can resist the rotation. Is that true? I think using big loose-balls with thin layer of grease ought to give you really free-rotating hubs. Not really silent though; should make some "shhh..." sound, and hubs gonna be screaming for repacking every so often. ...

I am all for low maintenance cost so,

My preference = Sealed Hubs

das_pyrate

exactly.

TL179

for real dude, go use some decent road hubs and see how they feel vs formula/surly/dimension. Its definitely tangible.

Tomo_Ishi

I have been studying some mechanics associated with ball bearings since the last post. Just reading wiki actually.

I think the guy's right in a way. If you can get a very high-quality loose ball hubs, you are going to have slightly better setup assuming the bearing balls are comparatively larger than those used for sealed bearings (1), the balls (and rest of bearing body) are perfectly smooth (2) and are packed with proper amount of grease and load pressure (3) .

It is entirely plausible that if you can guarantee those three things, you got yourself a hub that is better than a sealed-bearing hub in terms of durability and performance (over time). Maintaining the ideal bearing condition is gonna be tough, but it isn't impossible. Not that I would do it. I would like to spend more time truing and checking drive-train.

Additionally, don't forget about ball-cages. These keep distance between the balls so they don't interfere with each other. My current hub has cages, but my previous ones didn't. I know some people remove cages and pack more balls. Anyone have experience with that issue?

P.S. Crappo here is the hub I have.

https://www.fixiepixie.com/2008/02/un...rack-hubs.html

Caged loose ball, but it is sealed from outside. So sometimes people say it's "sealed" hub.