Do you think that the problem with stress risers would be problematic if the spokes were reversed on one side so that the spokes would be going the same direction as before i.e. keeping holes with trailing spokes trailing but on the other side of the flange, your quote states that the problem is partly due to the spoke pulling at 90 degrees from the initial lacing. I'm yet to find any info on keeping the spokes pull direction unchanged but reversing the side of the flange it pulls from.
Hi Iain!
I was so intrigued academically by your question, I went out to the garage, got an old wheel, and deliberately re-laced it to match the one you're considering so I could speak about the situation firsthand.
I've not used a wheel built like this extensively, so I don't have accumulated firsthand empirical data to say for sure, but...
I *think* you would be more likely to have a good outcome (and avoid a bad one) by going about it this way, but do be aware...the now-reversed spoke heads will sit in pear-shaped beds, and the bends will seat on the opposite side of the same hole. Depending on the spokes used and how the bends were formed and the heads forged, there can be a fairly deep trough formed in the hub tangential to the hole, caused by the tensioned spoke.
Speaking of tensioning, I think the risk of flange failure -- after the initial tensioning (here it could all go Crab Louie and become a wheel salad) -- would be less with a tight wheel than a loose one, as the tension cycles on the loaded spokes would be lower in amplitude -- the tight spoke won't move as much with each pedal stroke.
This is all speculation on my part and not an endorsement, but I think -- depending on intended and actual use -- you would get away with it if the wheel is built with high, even spoke tension. That said, there's many contributors to flange stress. If you're a spinner with fast, light pedal strokes and souplesse, they're going to have an easy life. If you're a masher with hard, rhythmic strokes on the pedals, that's a lot of stress cycles. If you're carrying heavy touring loads, climbing hills, standing on the pedals, using low gears...well, all those increase the risk of a failure, especially if the spokes are on the loose side.
For the kind of heavily laden, solo, back-of-beyond expedition touring on poor roads and cross-country I sometimes do, I wouldn't want to risk it. If I were doing credit card touring, riding reasonably and tootling 'round on day rides, I'd figure on getting away with it for awhile, perhaps indefinitely with my light. hummingbird-like high cadence. In those more benign environs, a flange failure might be an inconvenience that either doesn't bother much till you get home (think: equivalent of a broken spoke or two) or imposes an immediate limit on your tour that requires other arrangements to get home.
Rohloffs can be rejacketed with new shells and the guts transferred, but it will cost you. If that's needed, then the present bargain wouldn't be much of a bargain after all. Replacing the shell can be a bit complicated, as Rohloff doesn't want stolen hubs rejacketed and so won't sell the new shells to you direct. Instead, you have to turn your hub in to an authorized dealer and pay them to swap the innards. For a conversation elsewhere that is tangentially (sorry!) related to all this, see:
http://forums.mtbr.com/internal-gear-hubs/36-hole-speedhub-production-741399-2.htmlOne of the great virtues of the Rohloff hub is its overwhelming reliability. If you buy something that could compromise that, then it might not be worth the savings. OTOH, you could go for years or even decades without a problem, depending. I really can't say nor can anyone else, except to caution it would be better if the spokes had been laced correctly to begin with and didn't need to be reversed on the same shell.
Alternatively, you could use the hub as-is, and with even, high tensioning, the large flanges might prevent the torque-skewing I experienced on that 26in tandem wheel. That would be the most reliable approach, provided the rim stays put laterally under load. If you could try the wheel, you'd soon know or perhaps the seller would be candid enough to say. I suspect there may not be a problem, as the flanges are large, the spokes are short, and the rim small compared to, say, a 700C. Also, you might not develop the same peak torque loads as a loaded touring tandem pulling a trailer uphill under power in low gear by two people with in-phase cranks.
A final thought: So far as I know, Rohloff hub shells aren't forged with aligned grain structure. Instead, they are machined from billet by a sub-contractor under Rohloff's supervision. Grain-aligned forgings do allow a bit more leeway than billet machinings to try something sketchy without consequences.
Given my answer is largely conjecture, I think I'd try and find a similarly priced Rohloff without this lacing issue. They often show up at remarkably good prices *used* on German eBay, though of course without warranty and with unknown provenance. *New* prices there run €900-1100. Here's a custom search link for your convenience.
http://www.ebay.de/sch/i.html?_trksid=p2050601.m570.l1313.TR6.TRC1.A0.H0.XRohloff+Speedhub&_nkw=Rohloff+Speedhub&_sacat=0&_from=R40If the link breaks on wrapping, then try this TinyURL I made to get you to the same place:
http://tinyurl.com/kzjqhakI hope something in the above will prove helpful.
All the best,
Dan.
