Shelpi. here ya go .Bore x bore x .7854 x stroke x number of cylinders. The bore size MUST ALWAYS be first in this equation , The figure of . (that's point) .7854 is a constant in all cc calculations.
In your case that's 62 x 62 x .7854 x 54 x 2 = 326cc
Current engine in my 754 being 67 x 67 x .7854 x 65 x 4 = 916cc
Cheers Lucky front wheel from me
?
Suppose it did reach the finish line before everything else!!!