what is the physical difference between two stroke crankshaft and 4 stroke crankshaft for 4 cylinder engines i.e. how could we identify by just looking at the crankshaft i.e. one is of 2 stroke engine and another is of four stroke engine?
The 4 stroke version will have some means of transmitting drive to the camshaft. If there is a gear cast into the shaft, that's easy, but if the gear is removable - and not present - then some educated guessing is called for!
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