goatwarden wrote:In Shimano world this is all true. However Rohloff are indeed unusual but more importantly they make a complex product in low volume using unique components. Thus they can't afford to produce forged hub shells. Rather the shell, and thus the flanges, are machined from solid. So the flange cracking problem is a result of poor grain distribution around the spoke holes and, in my opinion, would be worse on a 36 hole version as each spoke would be subtended by a proportionately smaller area of material and so weaker. It is arguable that the stress on each spoke is also proportionately lower but in my experience the flange cracks due to an unusual load on individual spokes (in the case of my tandem, a stone hit one spoke causing it to snap and crack the flange at its base)
I was happy that Rohloff (via their Rolls Royce type warranty: "no it can't have failed,sir, its a Rohloff.") When they replaced mine with another 32 hole version. I believe that Rohloff still recommend the 32 hole version for tandem use. The 36 hole may give a longer fatigue life for lightly loaded (in comparison to a tandem) single bikes but not increased strength.
That's very interesting, the thought that while 36 spokes are better, 32 holes may be the better compromise due to flange failure. I would prefer to have a 36 spoke hub, but they are relatively recent, and I keep mine on a 26" wheel.
I have a bit of a love/hate relationship with my Rohloff, and am getting worried about it now, bought 2nd hand at a great bargain price. Mine is serial no. 007xxx, which apparently dates it to about 2000 or 2001. I got it after the original purchaser used it for only a few months.
When looking at Rohloff's website recently I came across these - Flange Support Rings:- http://www.rohloff.de/en/products/speed ... index.html
A forged hub shell would be much better I agree, they have sold a lot now and may be could have paid off the manufacturing costs by now.
2 weeks ago I rebuilt my wheel due to a mtb prang which wrecked the rim, wish I was aware of these support rings then as I probably would have fitted them as a precaution. I currently use the hub on an old mtb for racing (not very suited to the task I must say), but the same bike is my heavy duty bike when fitted with rack and mudguards too.
As aluminium is going to fail due to fatigue sometime, I like the idea of these rings and may get a couple to fit, may be even worth rebuilding the wheel before I need to.