I think it depends on whether your wheels are 700c, 27-inch, 26-inch, 650B, or 20 inchers (Bike Friday).

The diameter of the wheel is highly correlated with the amount of salt water damage that occurs, even if only the tire gets wet. The capillary action of the tiny hollow rubber molecules will suck the salt up into the tire and distribute it, depending on the size of the tire.

It also depends on what altitude you do this at. Most people think of "wheel dipping" as an activity that only occurs at sea level. But if you were to pack up several gallons of salt water, haul it to the top of the Continental Divide, and then pour it on your bike the corrosive effects could be completely different, because of the impact of elevation gains (if you want to try this experiment yourself, but don't want to carry several of gallons of seawater on your bike, you might try dehydrating the water at sea level and then re-hydrating it with snow melt when you reach a mountain pass).

Of course, you could also invert your bike, and dip the saddle instead. I believe in Vatican City they call this "the blessing of the Brooks," and is considered a source of luck for any cross-country journey. Given that the Vatican is so small one could cross it by bicycle in about 3 minutes, I'm not sure we should be taking the Pope's advice on long-distance cycling, but I thought it would be useful to ensure that all rituals were considered here.

Carry on...