This a genuine question, as I believe there is way too much misinformation.
I was reading (randomly) in a S2ki thread and many were commenting on the sizes of wheels and how they would affect gearing and handling.
For instance: A large wheel affecting gearing. Which I could understand if the bigger wheel also had the stock tire wall height. But what if the circumference of the tire remains the same with the addition of a bigger wheel? Does gearing still change?
As for track days and autoX, can some one chime in on how a bigger wheel affects handling why a smaller wheel would be more effective in those scenarios?
I understand that a bigger wheel can be heavier, reduce turn in speed, acceleration, and braking. But in many cases a larger tire weighs less than a smaller one.
What about bigger wheels that weigh less than stock ones?
I think that's it for now.

 

No, only total circumference changes effective gearing. Smaller wheels (assumes smaller circumference) means lower gearing which equates to more applied torque...car moves more freely.