Quote:
This is surely basic high school maths.
Cylinder volume is calculated by using the following formula. Use millimeters as this is the standard that was used when the engine was designed.

R squared x Pi x L [x number of cylinders if you want whole of engine displacement] divided by 1000.

Use a scientific calculator to get the correct value of Pi.
R= Radius [Half of the diameter of the bore]
L= The length of the stroke of the crankshaft

This will give you the displacement in cubic millimetres, so divide by 1000 to get cubic centimetres.
Too easy.