How do you figure out displacement using the bore and stroke numbers? Also a bigger bore will result in more higher rpm horsepower and a longer stroke will result in more low end torque right?

 

I think you are backwards.........bore = low end
stroke = high end

 

go to www. b l u e t r a x x .com and click calculators on the left and then go to displacement calculator. Thats the only way I know how.

 

pi x r squared x height = displacement (or volume)

YFZ450 = 439cc...

pi x (4.75 x 4.75) x 6.2

3.14 x 22.56 x 6.2 = 439.246

pi x (9.5cm x 9.5cm) x 6.2cm = 439cc

selector

 

Bore VS Stroke. Which would you prefer? Do you guys know why a huge truck can put out low RPM and still pull all that heavy stuff? Why is it that F1 cars put out really high RPMs and not be able to pull heavy loads?

A huge truck has a longer Stroke. It takes it a lot longer to make a cycle inside the cylinder so therefore there is low revving. An F1 car revs really high because it has a small stroke, but a huge bore.