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My bike has a hub dynamo in the front wheel. Recently I have replaced the old fork with a used one I got from my local bike club. The new one has fixing points for the cabling on the other side of the fork. Because the hub has only one connector for the wires, it would need to be installed contrary to the indicated running direction.
I recently saw this question, and it is partially answering my question. To follow up: How, if at all, does the dynamo change the situation?
The electric parts of the dynamo hub don't care. They're an AC generator and there's no concept of reversing the flow with AC.
However, the mechanical bits of the hub itself can be a problem. You don't indicate which manufacturer/model dynamo you have. The great majority of hubs are constructed such that they are expecting the wheel to turn in a certain direction in order to keep internal nuts and bolts tightened. Going in the opposite direction could lead to fiddly bits unscrewing themselves.
Where possible, I'd try to respect the directionality of dynohubs that have directionality. It would just take an extra length of wire or some zipties to snake the power cable around to the other side, it's worth that for the peace of mind to know that the hub won't self-destruct when you're going down a long hill.
Note: All Shimanos, all Sanyo, and older Schmidt/SON hubs are vulnerable to unscrewing if they are oriented with the power leads on the left (NDS) rather than the right (drive) side. Newer Schmidt SON hubs are flippable with the exception of the SON SL (below). When in doubt, ask your manufacturer/reseller.
N.B.: Some special (and expensive) dynohubs such as the Schmidt Son SL pair with specially designed forks so that no external wires are needed, but it also means you can't flip the wheel around or it shorts to ground. Assuredly that's not the case with you.
I contacted Shutter Precision to ask if their PD8 hubs could be run backwards. Here is their reply.
Thanks for riding with SP. It is ok to put SP hub in your way. It is ok to spin backwards. It may create more power a little bit than it spins forwards. More power will will also creates more resistance. It is fair….So please fasten the quick release tightly enough. If the QR is not fastened tightly enough, the connector will spin when the wheel spins. When you ride, the connector cannot move. It must stay at the fixed position. Feel free to let me know if you have any inquiries.
From the way a dynamo works in principle, I would expect it to work with either running direction. I would try that first and would not expect any long-term problems when it does work. If you provide details about the dynamo hub, maybe someone can comment on that model specifically. If it obviously doesn't work when turning backwards, I would change the cabling to the other side.
