Originally Posted by
Kimmo
...I'm always amazed this doesn't spark more discussion when I bring it up.
It should be obvious that the Shimano design is inherently much stronger, therefore able to be made significantly lighter.
Shimano disagrees.
Shimano dropped it at the Dura Ace level in 2004 because the smaller axle and hub/freehub connection weighed more than an oversized axle that was big and strong enough, thus copying the five year old design Campagnolo was using on all hubs down to the Centaur/Daytona level (which one could equate to 105 in terms of comparable price and positioning as third best) at the time (2000+ Mirage/Veloce are similar in concept, but use a smaller over-sized steel axle and cartridge bearings).
Shimano 2004 DURA-ACE FH-7800 parts diagram:
from
http://techdocs.shimano.com/media/te...9830728254.pdf
Campagnolo 1999 Record hub from 1999 spare parts catalog. The Chorus hub is identical but lacks the grease port and 10g saving titanium pawl carrier on the Record freehub. The skewer isn't as sexy looking either since it lacks the lever cut-out and D-ring equipped nut. In 2000 the design moved down to the Daytona level distinguished by an ugly skewer nut and remained unchanged until 2007 when the hub went on a diet (no separate pawl carrier, lighter adjuster) and Campagnolo stopped selling all but the Record 32 hole version when not built into one of their wheels.
http://www.campagnolo.com/repository...spares99-B.pdf
Significant differences between Shimano's 2004 flagship product and Campagnolo's 1999 are
1) Shimano cups and freehub pawls/springs are not available as small parts
2) The Dura Ace hub lacks a grease port so it goes half as long as Record before disassembly for service is required.
Otherwise they're nearly identical. Also note how Shimano copied Campagnolo's seven year old deeper spline design as used on all Campagnolo 9, 10, and 11 speed hubs to this date allowing the use of lighter but softer freehub bodies without the indentation problems that plague aftermarket alloy Shimano/SRAM compatible freehubs. All Campagnolo 9+ speed hubs made since 1997 have been equipped with aluminum freehub bodies that don't get notched even when using loose-cog cassettes (I have one from 97 or 98 that looks like new). The current titanium short splined Dura Ace freehub body won't get notched either, but results in a hub weighing an ounce more than today's Record.
Most boutique hubs use the same axle arrangement, although their makers are too cheap to make cup and cone bearings or contract out their construction. Nearly all also skip the investment in the spoke hole coining operation that Campagnolo and Shimano use.
I'm annoyed that there isn't a single boutique hub manufacturer I know of that licenses Shimano's patent in order to make the ultimate hub;
Cycleops used a Shimano freehub and drive side bearing on their original Powertap hub. The clunky Shimano steel freehub and hub/freehub interface had a lot to do with it weighing 160 grams (almost 1/3 pound!) more than the next generation Powertap SL.
IIRC there's no shortage of fancy rear hubs lighter than DA, no? So it should be possible to go lighter still with Shimano's design.
Hubs with 15mm aluminum axles and conventional freehub/bearing arrangement are strong enough, lighter, and less expensive to produce.
Shimano's drive-side cup in the freehub body was only a benefit until people realized they could mate a larger diameter axle (with stiffness proportional to the cube of diameter and corresponding increases in fatigue life) to standard-sized end caps (for compatibility with all the frames out there with matching spacing).