CHAPTER XII.

HEADERS OR CROPPERS.

“Taking headers,” or, in the parlance of our brethren of England, “coming croppers,” is perhaps a trivial heading for any article outside of newspaper or wheel periodical gossip, but it has a popular twang, and to the fraternity means a great deal. Every rider of the old Ordinary can give us personal experiences on this subject; among them will be found mishaps too serious to be chronicled in any jesting mood, a few so serious that we would fain forget them were not this forbidden by our sympathy and respect for the sufferers as fellows of our craft. From this sombre side of our story how joyfully we turn to the many humorous anecdotes which have been related in every club-room, in some of which “we ourselves were part of what we told!”

The subject would ere this have been obsolete were it not for a large number who still maintain the supremacy of the “Ordinary,” and those others who, forming an intermediate class between the old and new, have unfurled their banner as doughty champions of the “Rational.”

A header is the act of “going down on the other side,” spoken of in a former chapter, or, more definitely, it is the projection of the rider over the handle-bar to the ground in advance of his machine. It is a simple process, being a mere application of the physical forces of gravity and momentum. A moving body tends to keep moving in a line until stopped or deviated by some counteracting force. In riding a cycle a certain momentum is acquired and kept up against the resisting forces of friction, impact of air, road resistance,etc. Headers are a result of a counteracting force, generally caused by sudden impact against a stationary obstacle on the road, or by the forward wheel becoming suddenly locked through a failure in the axle-bearings to work, or by some clog in the wheel preventing it from revolving freely through the fork in which it is hung. There are modifications of the header action even in machines of the same sizes of wheels and same rake,—rake being a term recognized to express the angle of the front fork from the vertical. This rake has to do with the liability to headers only in so far as it regulates the centre of gravity of the system, “more rake” generally meaning that the rider is farther behind the vertical line through the front wheel axle.

In order to take a header, a certain centre of gravity must get beyond a certain line. This centre of gravity will vary in position in different machines, and the modifications spoken of cause the line to move in a way which is, I think, sometimes overlooked.

If we discuss the crank Ordinary, it will be noticed that when the front wheel is stopped in its forward progress, the frame of the machine together with the rider and all other parts of the system revolve about the centre of the wheel and cause an action within the system, the same as that of the forward wheel revolving backward through the fork. Now, it is just when such backward motion is prevented, that the gravity line moves and alters the conditions, decreasing the liability to headers. If the forward wheel can revolve backward through the fork, then, in taking a header, the system, exclusive of the forward wheel, will revolve about a point in the wheel centre; but if it cannot so revolve, then the entire system, including the forward wheel, must all tend to revolve about the point of contact of the wheel with the ground. Now, it will be seen in the latter case, or anti-header machine as we shall call it, that as the system tends to revolve about the point of contact, such point will constantly change;in other words, the wheel must roll onward, and the point of contact will therefore advance.

Header action, smooth road.

InFig. 1, in the annexed diagram, we show the distance forward and upward,atob, the rider must be thrown before he gets beyond the gravity line,g, in the Ordinary;Fig. 2shows the distance when the wheel will not revolve backward through the fork. In either case, the header is supposed to be taken on a smooth road and not against an obstruction; this can easily occur in vaulting into the saddle or in leaning too far forward. It will be noticed that the distance the rider is elevated, or, in other words, the amount of work done against gravity, is in both cases the same, but the distance forward he must be thrown is considerably greater inFig. 2. This is for the reason that while the point of contact,h, with the ground remains the same inFig. 1, inFig. 2the point rolls on toi. For more accurate illustration of the work to be done against gravity, and the distance forward the rider must be thrown, see the header curves in Figs.4and5, farther on.

We see, then, that the advantage which the anti-header(No. 2) has over the Ordinary machine (No. 1) is not so very great when in both cases a smooth road is considered; when, however, we consider the element of an obstacle in the path, the difference is much more in favor of No. 2. Let us compare the action of both classes of machines against a four-inch obstruction. In all cases the action of No. 1 machine will be the same,—that is, the wheel will remain in contact ath,Fig. 1, and the saddle will go on over, just as it does in the case of no obstruction at all. But in No. 2 the very act of taking the header must raise the entire weight and roll the system upon the obstacle, as shown inFig. 3.

Anti-header wheel action on obstruction.

The point of contact,h, over and beyond which the centre of gravity must be thrown, will not only move forward, as shown in Fig. 2, but will move to the top of the obstaclei,Fig. 3. Or, if the question is one of a rut or indentation in the surface of the roadway, No. 2 will be caused to roll partially or altogether out of the rut. Now, since the rider, by the action of his momentumand that of the machine, is rolled upon the obstacle or out of the rut, it is easily seen that if he is attending strictly to his work and is at all a skilful rider, he can, by a lively thrust upon the pedal at the opportune time, right himself and keep the drive-wheel rolling on, in which case the rear part of the machine will, in all ordinary cases, drop back upon the ground, from which, of course, it will have raised.

Ordinary header curve, any obstruction.

Anti-header attachment, smooth road.

Anti-header, four-inch obstruction.

Anti-header, eight-inch obstruction.

In the diagrams herewith annexed,Fig. 4shows the curve of the saddle of a No. 1 (Ordinary) machine on a level road, and which would be the same against any obstruction. Scale, one-sixteenth.

Remark how the rider must be lifted from the levelctoband be thrown forward fromatob.

Fig. 5shows the curve of a No. 2 machine, with the anti-header device, on a level road. The elevation and forward throw are represented by the same letters as in Fig. 4; it will be noticed that the distance fromatobis very much increased.

Figs.6and7show the curves or necessary projection, forward and upward, of the saddle in the header act of a No. 2 machine upon four- and eight-inch obstructions respectively.

The feature of a non-backward revolution of the drive-wheel through the fork is a natural consequence in some lever and clutch machines. This element of anti-header has been the subject of an invention in the way of an attachment to the Ordinary, contrived with a view to reaching the same result, but it cannot be said to be a successful venture in the market, the probable reasons being, first, that it interferes, to a slight extent, in managing the dismounted wheel, the operator being unable to run it backward, as is sometimes desirable; second, that the anti-header element has not been really understood or appreciated among the fraternity, as it does not appeal to the judgment of the casual observer that any such element results from the fact “that a wheel won’t run back.” In the lever and clutch machine a third objection is raised,—the rider cannot back-pedal, but must depend entirely on the brake in descending hills.

Header Rational Ordinary.

Header Kangaroo.

Kangaroo anti-header, four-inch obstruction.

Header Star rear-driver lever machine.

Header Rover rear-driver type of machine.

Fig. 8shows the Rational Ordinary curve;

Fig. 9, the curve made by the well-known Kangaroo;

Fig. 10, the Kangaroo with clutch or anti-header attachment;

Fig. 11, the American Star combination of wheels;

Fig. 12, the curve of the regular crank Rover machine.

The Rover type of safety machine is practically free from the liability to direct headers, for the reason that the centre of gravity of the system has to be raised to such a height that the rider swerves around sideways before he can go over; nevertheless, a modified form of the same might be possible through some remote concatenation of circumstances causing the machine to stop and throw the rider bodily over the handle-bar without keeping him company on the trip as usual, inwhich case he, at least, escapes the usual subsequent annoyance of being pounded by the rear wheel.

A header cannot result from stopping the rotation of the rear wheel, as generally supposed, because the point of contact of the same being in the rear of the rider and centre of gravity, the system cannot revolve about the said point in a forward direction, or direction of momentum. It will be seen, then, that if from any cause the rear wheel leaves the ground, which it can do from a rebound against some obstruction, the instant it does so the system will be simply carried forward by the rolling of the front wheel.

Headers have been said to result from the above cause in the ordinary bicycle, but the writer after several experiments has been unable to attain such a result. Yet it is quite possible that it might occur from the rebound of the rear wheel in striking an object with great force, though it is altogether improbable if the drive-wheel were kept fully in motion. An obstruction so great as to bodily raise the wheel sufficiently high to throw the centre of gravity over never gets a chance to act, since the forward wheel must surmount it first, and this is where the header occurs. It can be easily seen that when the rear wheel, from any cause, is raised from the ground, there can be no action within the system to make it raise any higher or to prevent the forward wheel from rolling onward as usual; hence it is evident that as soon as the former leaves the ground it will simply drop back and rebound again at will. But in the other case, if the front wheel is locked, the rear wheel cannot go on in a straight line and it must therefore go on over the top.

In the writer’s experiments on the rear wheel, he had an attendant throw a stick between the spokes while in motion; it was not tried at very high speed, however, for the reason, perhaps, that any failure in the theory above provided might end rather disastrously to the experimenter and thereby cause an act of ingratitudeto be perpetrated upon the prospective patron of this book, through an inability to ever finish it.

If some ambitious cyclist will kindly complete these experiments, the writer will gladly incorporate an account of them in future editions of this work, together with an appropriate obituary notice in large type.

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