Dura ace 7800 rear hub sealing

[tommy]

I don't know if this topic has been discussed but i just want to know if somebody had any experience with this:
Last week it was raining like hell when i had to race... I thought i will use my wheels with da7800 hubs because they are supposebly sealed very well. After the race (165km) I cleaned the wheels oiled the cogs and put them in their bags. Today i take them out of their bags to check if the tubes are still good enough to race. i want to spin my freewheel: STUCK
I put the wheel in my bike and even then a can't get my freewheel to spin!
So i take of the casette and spray a rust desolvent that is also a lubricant on and in the freewheel.
Eventually i had it spinning again but there was a big amount of rust that came out of the freewheel.

Ok maybe i should have done this directly after the race but i have never seen something like this. Can't say that i'm pleased of the sealing nor the type of grease in the freewheel because the hubs are only used 4times!!!

[Mark McM]

This not a direct answer, but a related observation.

The new DA 7800 freehub is nearly a copy of the current Campagnolo hubs, with their oversized aluminum axle, inboard right bearings, and ratchets located in the hubshell (under the right flange). When Campagnolo first released their inboard-bearing freehub design (about '92, IIRC), they had a lot of problems with water leakage into the pawls and right side bearings, which is an unfortunate feature of this design. They eventually modified and improved the sealing system, so their latest hubs are reasonably reliable in this regard. Maybe Shimano is just starting up the learning curve with this type of design?

[leonardo da vinci]

After the race (165km) I cleaned the wheels oiled the cogs and put them in their bags. Today i take them out of their bags to check if the tubes are still good enough to race. i want to spin my freewheel: STUCK

Hey Tommy, I don't think that putting wheels away in their bags is the best idea. Of course, one wouldn't expect these hubs to fail in this manner, but putting moist equipment in a bag...

[tommy]

They went dry in to the bags! atleast the outside
the wheels are cleaned with a special product witch removes water and dirt(like some lubricants) . There is no water used with the cleaning of the wheels.
And even if i would wash them with water i would let them dry first and the bags are always left open...

No, the problem with these hubs is that the casetteside of the hub is not sealed good enough to prevent water getting in to the freewheel.
Now that i know this, i wil not use them anymore in rainy weather.

I have always used my ksyrium sl's for bad weather, never had any problems... rode my first time in bad weather with the DA and... well you all read what happened...