Quote:
Originally Posted by CT
Total wheel weight and moment of inertia aren't completely tied together. Incoming maths!
A large portion of the wheel's mass is the rim itself, not the hub-mounting face and spokes, and that's the portion that's farthest away from the center of rotation. I = mass * dist_to_center^2 (in general for a thin-walled cylinder). For a two-piece wheel, a 19" rim will have a MoI of about 11.4% more than the 18" rim. The face/spoke center piece will also have a somewhat larger MoI, though maybe less pronounced. MoI is used to calculate the energy needed to maintain or change motion (e.g. go fast or stop going fast).
This also discounts the additional weight / MoI of the 18" tire combination you would need to run, but the overall mass of the added tire is very small and, at the radius at which you are adding material, does not span the entire width of the wheel providing for a relatively small MoI.
|
where are you coming up with your numbers for your math???