Cracked hub flange

[The Hegelian]

Yesterday whilst riding slowly up hill, the rear hub flange cracked on my cross bike. I've been riding for 25 years, and never even had a broken spoke.

A few questions:
1. What could be the cause? It's definitely not my immense power!
2. Is this likely to be covered by warranty? The bike is less than 3 years old.

 

[JayKosta]

It might have cracked due to a defect in manufacturing. It would take an examination of the crack to determine if that's the case - e.g. voids or bubbles in the metal where the crack happened.
Or it could have cracked due to some external damage done to the hub - gouged with wrench, dropped, etc.

I doubt that it's covered by any general warrenty - you'd have to convince someone that it was defective and not due to normal wear / usage.

Jay Kosta
Endwell NY USA

 

[The Hegelian]

Thanks Jay.

I think it probably was a manufacturing fault - if only because the bike doesn't have many k's on it, hasn't been ridden hard and hasn't received any external damage.

I have contacted Fulcrum, but frankly I'm not holding my breath. It may be that there have been other failures of the same kind on the same wheelset, in which case they may take responsibility, but if it's a one off I don't like my chances.

 

[smith931]

Some hubs have had that problem, are known to crack at the flange. When we looked at why they broke, we found the worst problems in hubs made from harder alloys. Once I had one break apart on the drive side while riding in a fast group on a smooth road. It could be the build and spoke tension, but hubs are made of metal and sometimes there are flaws in the manufacturing or metallurgy that aren't readily apparent. Fortunately, it's very rare.