We take a look at 16 sets of motorcycle wheels and explain the ins and outs.
Few aftermarket items can change your bike's performance as drastically, and in so many respects, as a set of wheels. The few pounds dropped would hardly be noticeable if they were from another part of your bike, but because that weight is unsprung and spinning, the effects are magnified greatly. Add in the fact that sexy wheels are out in the open for everyone to ogle, and you can appreciate their popularity.
Testing wheels is difficult-the benefits felt are very subjective-and there is a mind-boggling assortment of aftermarket hoops to choose from. For starters, there are many sizes and types of wheels depending on what kind of riding you do-or how you want your bike to look. A street rider has no use for 16.5-inch race wheels, as there is zero DOT tire selection for them (and don't hold your breath for that to change-the truck industry is still feeling the effects of the dangers associated with having available rim sizes just a half-inch apart). A racebike with carbon-fiber wheels will not pass inspection in most organizations, yet that may be the material most suited to track use. And a racer needs 16.5-inch wheels if he wants the latest in slick-tire technology.
That said, certain properties can be measured to define a wheel's characteristics. One aspect is obviously its weight-which affects both straight-line acceleration and suspension-but another is its Moment of Inertia (MoI)-the characteristic that determines how great an effect that weight has when it is spinning (see sidebar, page 43).
To settle on a base line of what wheel sizes to test, we contacted as many manufacturers as we could find and asked for 17.0-inch hoops for our GSX-R1000 test mule in 3.5-inch front and 6.0-inch rear widths. Each manufacturer was invited to submit two sets, one oriented toward the street rider, one for track use. And yes, we know serious track wheels would be 16.5-inch, but in the interests of comparing apples to apples....
We weighed each wheel using an AdamLab CPW30 scale (measuring to 0.02 pounds, or one-third of an ounce), and found its Moment of Inertia. To check fit and finish, we mounted each set to the bike and measured some important dimensions. We'd have loved to test for strength and elasticity, but turning $30,000 worth of wheels into junk would make mincemeat out of our budget. Finally, we rode the GSX-R at a track day with one of the lightest sets of wheels installed to see just what all the fuss is about (see sidebar, at the end of this article.)
And now, a healthy host of heavenly hoops harmoniously and humbly harvested and highlighted for your honorable henpecking. Honest!