Kunstgriffe beim Messen: Unterschied zwischen den Versionen

For internal threads, remember that you are looking at the back of the threading, and so the slant is opposite.

For a quill stem, the only sizes that are anywhere near each other are 21.15 mm -- mostly on BMX bikes; 22 mm (French, no longer made), or 22.2 mm (7/8 inch) -- the usual size. These can all be tested with a 7/8 inch open-end wrench or a fork which you know to have the usual 22.2 mm dimension. Any fork with a steerer tube about an inch across and 24 TPI threading will do. The usual 22.2 mm stem will be a nice slip fit, the French stem will be slightly loose, and the BMX stem, very loose. A French fork will usually not fit the 22.2 mm stem, but the French fork steerer will be only very slightly too small. The only other common quill-stem diameter is the 25.4 mm (1 inch) size used in 1 1/8" head tubes.

For clamp-on stems, the fork steerer is 1", 1 1/8", 1 1/4" or 1 1/2 inches, all different enough that they can easily be identified with a ruler, and confusion is hardly possible.

==Schnelles zählen von Zähnen eines Kettenblatts oder Ritzels==