@BILL S
Looking at this I'd say you're suffering from delirium of swiftness.
Advice from the American Medical Association (in 1895):
"Ride no faster than 12 kilometers an hour [and] as far as possible, guard against the desire to ride any faster. It is very difficult not to give way to the 'delirium of swiftness.' With a light machine on a good road an amateur may easily make 25 kilometers an hour. This is too much, for the pulse is increased to 150, even at 14 and 16 kilometers per hour."
The "Bicycle Face"
—In the midst of the ceaseless paeans of praise to the bicycle as one of the most health-giving institutions a faint voice of warning sometimes is heard. Thus a recent medical writer in the St. James' Budget, while not denying the undoubted virtues of the bicycle exercise, points out that not all riders present that healthful appearance one might look for, and in fact there is seen among their number a type, ashen-hued and haggard, already recognized as the "bicycle face." Not so with tricycle riders—and here is where he looks for an explanation.
The distinguishing feature of the bicycle, and especially of the safety, this observer claims, is the difficulty of maintaining the equilibrium. "Learning" to ride, means mastering the art of keeping the machine upright. It has a tendency to fall to one side or the other all the time, which has to be counteracted by a special effort. The learner knows it very well to his cost; but once learned, he forgets about it, and does his balancing more or less automatically. Nevertheless, the effort is still there, and puts a constant, though unconscious, effort upon his brain and nervous system.
The reason why the bicycle has to be "learned" at all, is that the center of equilibrium in the brain requires to be taught the business of doing its duty under novel circumstances. The falling bicycle is maintained upright by a constant series of small muscular movements, which unconsciously adjust the weight in the proper position and are themselves controlled by a special brain-center, situated at the back of the head. The strain upon this center is incessant, though unmarked; and some people can not stand it for more than a short time. This it is that causes the headache and the nervous exhaustion.
Probably it does not affect those who begin very young, and possibly it affects those with either very tough or very dull nerves but little. Most of us, however, are obliged to live in such a way that our nervous systems become very susceptible to any unaccustomed strain, and those who are most likely to use the bicycle belong to the most susceptible classes. The nervous effort entailed by balancing the machine is too much for them. The explanation may strike some people as fantastic, but it is sound physiology, and it squares with the facts. Experienced cyclists often say that the tricycle, and even the old high bicycle—which requires less effort to balance—are less fatiguing for prolonged work, such as a tour, than the safety; yet the latter is lighter, quicker, and superior in nearly every respect, save that of stability. It is a question of balance.
. Durations from an hour to a couple of days. No rhyme nor reason could be found, the family trait for hearing impairment has not helped. I think mine could have been BPPV.
