V-twin engine 75° crank pin offset for the rest of the world. Generally, a two-cylinder engine with the cylinders arranged at any angle greater than zero degrees and less than 180 degrees may be classified as a V-twin, although an angle that approaches zero is not practical. Despite Ducati referring to its 90 degree twin cylinder engine as an "L-twin"—with the front cylinder nearly horizontal and the rear cylinder almost vertical, there is no technical distinction between V-twin and L-twin engines. Assuming correct counterweighting, a 90 degree V-twin will achieve perfect primary balance. However, the 90 degree layout will produce an uneven
61 cm Type 90 torpedo 61 cm Type 90 torpedo The 61 cm Type 90 torpedo was a surface-fired torpedo used by the Imperial Japanese Navy during World War II. It was used in the s and in most cruisers, including the , , , and heavy cruisers after refits during the 1930s. It was superseded by the Type 93 oxygen-powered torpedo, commonly called the "Long Lance", as oxygen generating equipment was installed aboard the cruisers. The torpedo was based on a newly developed British Whitehead torpedo. This weapon used a new double-action two-cylinder engine rather than the four-cylinder radial engine used by World War