Great topic guys.
Always made me wonder why domed/hemi piston and chambers are used by manufacturers as well. There will be more surface area to cool and exert force downwards with a dome.
I think of stroke like the pedals of a bike. Longer ones are a longer lever arm, so they will make more torque at a lower rpm. Piston speed will be faster with a longer stroke, so parasitic losses will be higher-inertia and friction. Use a 4 ft pipe on the back of a monkey wrench (no offense Randy) and you're gonna move something less distance but with greater force than a 1 ft bar. It will just take you longer to do so.
Bigger bores allow for more port surface area. That's why I always want the bigger bore on a model. It's not always because of the displacement increase.
The 038 vs. 044 issue has always boggled my mind. The 038 is more of a torque Saw than an rpm Saw, but it's more oversquare. It's likely the porting that makes the difference than the geometry itself.
Bigger bores also cool less effectively than smaller bores. There's less surface area of fins in relation to bore. Less heat needs to be added for combustion efficiency, hence why smaller bores like more compression.
