Tandem chains are very much lighter than in former years, some makers using as light as 3⁄16 chain all over, but the majority of them use 3⁄16 for the front chain and ¼-inch for the rear chain. The combination tandems on the market are furnished usually with 20 or 22-inch front frame and 24-inch rear. Diamond frames are furnished either in 22 or 24-inch frames, 22-inch frames being in line with the prevailing fad of low frames, and therefore the most popular. Gears run from 80 to 120, the popular stock gear usually furnished being about 84, with 7-inch cranks.
On the [Wolff-American tandem] the diagonal stay carrying the seat-posts are not raked at the same angle with front fork and head. The middle steering post, however, is raked at the same angle as the head, thus permitting the rider in front to have more room for a better position in pedalling. The Wolff-American tandem is fitted with a very powerful rear brake. It consists of a lug which is brazed in the centre and underneath the main upper tube in front of the rear rider. From this lug a lever is hinged; this lever carries an adjustable wire rod to the brake spoon which is hinged on the bridge between the rear forks. Pulling up on this lever draws a powerful spoon against the rear tire. One of the advantages of this brake is that it does not affect the steering as a handlebar brake does.
The “World” tandems have an extra lower chord running from the front diagonal stay to the rear diagonal stay, which is in turn braced by two braces running from it to the lower chord of the frame. On the Dayton tandem an extra tube is carried from the head underneath the main upper tube and which intersects the diagonal tube and runs from there to the rear crank-hanger bracket. This construction produces a very stiff and rigid frame. On the Stokes convertible tandem an extra tube runs from the upper part of the head intersecting the front diagonal stay and the rear steering tube and is then brazed to the lower main tube. The Eldridge diamond tandem carries an extra tube from the front diagonal tube to the rear crank-hanger, and this same method of construction is followed in the Clipper convertible tandem.
In the Niagara tandem the top tube is paralleled by a tube placed about six inches below it, running from the front diagonal tube to the rear diagonal tube, the rear steering post intersecting it. On the Winton tandem the upper main tube is not continuous, there being an open space between the front seat post and the second steering post, this being braced, however, by a tube which runs from the front seat pillar, bracing the middle steering post, and running to the crank-hanger bracket. The Geneva and the Demorest are of the same construction.
The Columbia combination and diamond frame tandems are of the same general design as the 1897 models, except that it has been deemed advisable to have the frame connections of the external joint style instead of making them flush joint, as last year. On the diamond frame they run an extra tube from the lower part of the head, and this is connected to the front diagonal tube at a point about eight inches above the crank-hanger. This tube then runs horizontally, intersecting the second steering head, and ends at the rear diagonal stay, from there, however, a second pair of rear forks running to the back stays. This same construction is followed out in their combination frame, with the exception that the front part of the frame is of the double loop pattern, as in their single wheel. The Iroquois tandem has the same open construction at its front diagonal and second steering post as the Winton, heretofore mentioned.
WOLFF-AMERICAN
TANDEM.
The Tribune tandem has an extra tube, which parallels the main upper tube. On the Pierce double diamond tandem an extra tube runs from the middle of the head and intersects the front diagonal, and is brazed to the rear crank-hanger. The Henley diamond tandem has the upper main tube paralleled by an additional tube, which runs from the lower part of the head to the rear diagonal stay. On the Andrae tandem the chain adjustment is effected by means of eccentrics in both hangers, thus doing away with the slot in the rear fork ends, which has a three-eighths-inch opening, in which the three-eighths-inch axle is fitted perfectly, so that the rear wheel is perfectly centred at all times, even under the greatest strain. The method of placing an extra tube running from the top, or near the top, of the front diagonal stay to the crank-hanger bracket is in almost universal use, so that it is easier to name those who do not employ this method than to name those who do. Among the notable exceptions to this method of construction are the Columbia, Niagara and World.
Very few of the makers of tandems have made any great changes in their ’98 construction, the majority of the tandems shown being their ’97 product, somewhat improved in detail only. Handle bar fastenings are about nearly divided between the old-fashioned pinch bolt and the newer idea of internal clamp fastening. Some difficulty has been experienced in previous years in holding handlebar stems and seat posts securely in place on tandems, many of the makers not having used connections heavy enough and stiff enough to withstand the double pull that a tandem gets at these points, and the purchaser of the 1898 tandem should look well to the construction at these points before purchasing.