Dura ace 7850 rear hub problems - Page 2

Wait...are you saying that Shimano built that hub so that the freehub/pawls can't be serviced and has to instead be replaced? If that is the case, that's just one more reason to not by Shimano. It is hard, though, to believe they'd do that.

__________________
Sex is horrid
Pain is Fun
I cut my fingers off
One by one

Why would you intend to service the pawls? The new hubs 7850/7900 have put the pawl mechanism further "inside". Less of a service issue, if at all.

This is the same design used in the 7700 hubs introduced in 1997.

I want as few throw away parts as possible. A hub should be serviceable, even if that means replacing a pawl, a pawl spring, whatever. Pawls have broken before, and so have springs, in the history of cycling.

__________________
Sex is horrid
Pain is Fun
I cut my fingers off
One by one

Yep, the 7850 and 7900 are the older style, sealed in a unit, freehub, like 7700, 7400, ultegra, etc. A step backward, IMO.

Two sides of the same coin. Different models, distinct style/design. Nothing backward about it.

Exposed freehubs, like Campagnolo, can be serviced, pawls, springs and bearings replaced. This design is throw away, titanim to boot. I think to throw away a titanium freehub that quits working(any many of this design does) and have to spend $150+ for a new one is a shame. Where $20 of bearings and $10 of pawls and springs would fix a Campagnolo one, for instance.

BUT that is shimano's MO anyway...STI.....

It's not like the way you describe. Your description has a flair for the dramatic. The point was made 4 posts ago in this thread.

Now if you're complaining about sealed freehub bearings also, 7800/7801 have sealed freehub bearings, and no one is complaining about those.

hi
i'd never asked myself how a freehub + cassette worked... nice to learn it. I had that cracking sound also once in a ride in my commuting bike, on a low end shimano hub. I didn't give it much importance until one day the hub broke down (freewheeling in both directions). LBS replace it and said it couldn't be serviced.

How is it?

They have 'cartridge bearings' and they have 'seals, but they aren't 'sealed'.

The 7850 and 7900 cannot be disassembled and reassmbled ala all other freehub bodies that have replaceable 'cartridge' bearings in them, As far as I know.

http://www.sheldonbrown.com/brandt/sealed-bearings.html