Читать книгу The Modern Bicycle and Its Accessories - Julius Wilcox - Страница 15

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The use of large tubing seems to have reached its limit during 1897, a majority of the makers now using 1⅛ inch tubing in the front part of the frame. Other makers vary this, of course, by using 1¼ inch tubing in the lower main frame, and in the diagonal stay which runs from the crank-hanger bracket to the seat-pillar cluster; D-shaped tubing, however, is much more largely used than before for rear forks and back stays. Front forks are also largely made of D-shaped tubing, many of the makers using a front fork made of an internally tapered continuous piece of D-shaped tubing. Rear forks are also made in this same manner, and are connected to the crank-hanger by a single large round stem, which avoids the necessity of offsetting the fork on the chain side. Back stays are also connected to the main part of the frame in this same manner. This idea, when used in connection with the arch-front fork crown, which is the most popular one of the day, and which seems destined to supersede entirely in popular favor the old two-piece crown, makes a very taking looking construction. There is, however, a question as to whether this method of joining the continuous rear forks to a single stem is as rigid as would be two separate forks, run either straight or with an offset to the crank-hanger.

Internally tapered tubing is very largely used in frame construction generally, thus avoiding all need of employing internal reinforcements or liners, as formerly, which are liable to cause the tube to give way under strain at the exact place where they come to an end. This is considered a step in the right direction.