Should you go with the powdercoated or chrome-plated wheels? How about a sporty five-spoke wheel…or maybe the classic smoothie look?
Yes, style and finish are important considerations when choosing a new set of rims, but bolt pattern, backspacing, and offset are absolutely crucial. Outside of the physical size of the wheel, these are the three most-common measurements used to match the right wheel size to a particular vehicle. We’ll cover the basics of wheel offsets now–look for a post on bolt pattern and backspacing in a later post.
Offset vs. Backspacing
Offset and backspacing are similar measurements. While backspacing is the distance between the back of the rim flange and the hub mounting surface, offset is the distance between the centerline of the wheel and the hub mounting surface. Measured in millimeters, offset is the measurement of choice for many custom wheel manufacturers.
Positive vs. Negative Offset
A wheel can come with a zero offset, positive offset, or negative offset. Zero offset occurs when the hub mounting surface is even with the centerline of wheel. Most factory rims come with a positive offset, which is achieved when wheel manufacturers place the hub mounting surface to the street side of the centerline. Most front-wheel drive vehicles use positive offset (or dished-out) wheels; most rear-wheel drive vehicles have negative offset wheels. Negative offset wheels locate the hub mounting surface to the brake side of the centerline, giving them a “deep dish” appearance.
Choosing the Right Offset
If the wheel offset is not correct for your vehicle, handling can be adversely affected. For example, excessive negative offset can cause steering wheel kick-back and place additional stress on your vehicle’s entire suspension. Talk to your sales rep or wheel manufacturer to help you determine a range of acceptable offset ratings for your vehicle. When you receive your new wheels, test fit them on your car or truck before mounting the tires. Once the tires are mounted, the wheels can’t be returned.
[…] this quick quide to measuring wheel bolt pattern and backspacing. Along with our articles on wheel offsets and wheel/tire plus-sizing, this information will help you take essential steps toward selecting the […]