Anyone use Zipp Z4s or Z3s instead of 404s and 303s. I was wondering if there is really any difference? How much of an impact does the cermic bearings really have? This is not a cost-benefit question, just a curiousity question.
Thank you in advance for your help and information,
Neal Dunn
The main benefit is to Zipp and their dealers who make a lot more money from selling them.
Last year the Kilo at Worlds was won by .001 of a second.
With ceramic bearings, he could have had a more comfortable margin of victory, like .01
They’re for people who need toys, not speed.
Ceramic bearings generally have slightly lower friction and slightly longer life than steel bearings. But the differences in actual bearing friction would be such a small component of the forces resisting motion on a bicycle as to render them inconsequential. If you have regular 404’s and you want to go faster, sell them and spendd the money on a Hed3 and a disk, not exotic bearings.
I have a 2002 Zipp disk and the overall wheel is amazing but the hub is below average. It has higher friction than my Campagnolo and Mavic wheels and is difficult to adjust. If the Zipp ceramic bearings come with a different hub mechanism that is more reliable and easier to adjust than the 2002 and earlier hubs, then they might be worth something.
To be specific, the root cause of the problems in the 2002 model is that the hub is held together by with tension between the dustcap and the hub body. You either have a smooth hub with a bit of play and a gap between the dustcap and the hub body or a tight hub with high friction. If you adjust the hub to be fast with play, there will be no tension on the axel nuts and they will work their way looser and looser. There should be a locking mechanism of some sort to set and fix the dust cap tension independent of the hub body.
Disclaimer: I noticed that the 2003 Zipp disk had a different looking hub than the 2002 one I own, so it is possible that they have already fixed this in the current models.
My thoughts are that the Z4 is for guys who like to have the best, think that these flashy wheels will get them respect from the other guys and will somehow make them seem more attractive to chicks. For these reasons I was drooling over them on the Zipp website earlier today 
The reason I say guys only, is that girls seem to have more sense than us when it comes to buying these kind of toys. Of course, girls lose all their sense when it comes to stuff like clothes, so it all kind of evens out.
Bottom line in my opinion, they look hot and if you think they are the best, there’s every chance you will go faster but you’ll be paying a hell of a lot for the pleasure.
$1700.