I think I finally found the wheels that I want but am having a hardtime wrapping my head around the offset vs. backspacing and how the numbers are determined. I've seen the FAQ's and while the explain it, it still doesn't make a whole lot of sense in trying to determine what the backspacing is given just the wheel size and offset. If I am figuring it right, then the wheel below would be 4.25 in backspacing plus the 18mm (3/4 in) offset for a total of 5 in backspacing? I've seen that the recommended backspacing is between 3.5 and 4.5. What is the extra .5 in going to affect?

http://www.voxxwheel.com/component/v...&category_id=1

Thanks!

 

I am not an expert, but I just went thru the exact same exercise. What I learned from an expert is that there is no precise way to convert offset to backspace. Offset is a true measurement that is consistent from wheel to wheel. Backspace can vary from manufacturer to manufacturer because it includes the thickness of the "lip" of the wheel, which varies between wheels.

So while you can get "close" to backspace from offset (and vice versa), you cannot get exact. And I needed exact because of a clearance issue at the rear fender flare. A .5" difference for me would have been the difference between just a slight "kiss" of the flare to a major rub issue at full stuff.

Hope that helps...........................

 

BS is distance from axle mount to inside edge of rim. Offset is how far off from the center of the wheel the axle mounts. Thus, offset can be pos or neg, BS is always pos. Google it and look at an image with BS and offset labeled.

 

You should not add that .5" into the BS as they are measuring different characteristics of the wheel. As an example, a wheel with 0.00" offset will have the axle mounting in the center of the wheel and the BS will also be equal to the distance between the outer lip and the center.