Copio da Wikipedia:
Crossplane crankshaft could be used in many cylinder configurations to have an evenly spaced firing as long as the number of cylinders is multiples of four in two-stroke engines, or multiples of eight in 4 stroke engines. Unless the crank pins have big-end phase-offset, the V-angle requirement must be met for an evenly spaced firing on V configurations as listed below.
2 cycle: L4, L8, L12, L16, V4 (V-angle of 90°), V8 (45°,90° or 135°), V12 (30°,60°,90°,120° or 150°), V16 (22.5°,45°,67.5°,90°,112.5°,135° or 157.5°), flat4, flat8, flat12, flat16, etc.
4 cycle: L8, L16, V8 (V-angle of 90°), V16 (45°,90° or 135°), flat8, flat16, etc.
However, crossplane crankshaft has been used on other 4 stroke configurations like L2, L4, V2 and V4 engines with unevenly spaced firing when its prominent advantage of smaller secondary (non-sinusoidal) vibration, which increases exponentially with crankshaft rotational speed, out-weigh the disadvantages like the imbalance in firing spacing and the increase in rocking vibration.
Abbastanza chiaro, no?
Crossplane crankshaft could be used in many cylinder configurations to have an evenly spaced firing as long as the number of cylinders is multiples of four in two-stroke engines, or multiples of eight in 4 stroke engines. Unless the crank pins have big-end phase-offset, the V-angle requirement must be met for an evenly spaced firing on V configurations as listed below.
2 cycle: L4, L8, L12, L16, V4 (V-angle of 90°), V8 (45°,90° or 135°), V12 (30°,60°,90°,120° or 150°), V16 (22.5°,45°,67.5°,90°,112.5°,135° or 157.5°), flat4, flat8, flat12, flat16, etc.
4 cycle: L8, L16, V8 (V-angle of 90°), V16 (45°,90° or 135°), flat8, flat16, etc.
However, crossplane crankshaft has been used on other 4 stroke configurations like L2, L4, V2 and V4 engines with unevenly spaced firing when its prominent advantage of smaller secondary (non-sinusoidal) vibration, which increases exponentially with crankshaft rotational speed, out-weigh the disadvantages like the imbalance in firing spacing and the increase in rocking vibration.
Abbastanza chiaro, no?
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