At about 7000 rpm the piston exceeds the engineering limit for piston speed, so over-revving soon destroys the engines.
The Triumph, with its shorter stroke, had a mean piston speed of only 3,497 ft/min, had much less vibration and was much stronger and reliable.
The square bore and stroke lowered piston speed and promoted crankshaft rigidity, no small matter for an engine with eight cylinders in line per cylinder bank.
This limits the piston speed for industrial engines to about 10 m/s.
This is because improvements in valve design allowed for higher piston speeds.
The Shadow's fist came up with the same piston speed of the brass coils on Hebler's desk.
Oversquare engines (a.k.a. "short stroke engines") are very common, as they allow higher rpm (and thus more power), without excessive piston speed.
For paddle ships the piston speed was estimated as 129.7 x (stroke)
Such early engines, constrained by the technology of the time, worked at low boiler pressures and slow piston speeds.
Its French author had been stressing the importance of high piston speeds and the necessity of good breathing through large valves and a free-flowing exhaust system.