Originally Posted By: SilverFusion2010
I've got mixed feelings about bigger rims. On the one hand you get better cornering because the tire is lower profile, but man are 17" tires pricey.
AFAIK:
A bigger wheel with a lower profile tire CAN improve cornering, but only in one respect: less sidewall movement, making things slightly sharper and more consistent. But that's only all else equal. A bigger wheel needs to be more rigid or it'll flex, and it needs to be lighter or you'll get gyro effects and all the other problems with unsprung rotating mass. Needless to say, a bigger wheel with the right strength and weight vs. a smaller one gets awfully expensive.
A stiffer tire sidewall can give you all the rigidity you need while letting you run a smaller rim. So, in the abstract, there are only two reasons for a bigger wheel:
1. Clearance for bigger brakes, and
2. Looks.
Of course, it's now getting to the point that the best tires only come in large sizes. Tire selection for small sizes is really starting to suck. Bit of a vicious cycle.
IMO, with VERY few exceptions:
- If a passenger vehicle needs wheels bigger than 17" to look right, it's too big; and
- If it needs brakes that wouldn't fit under a 17" wheel, it's too heavy.