05-28-2014, 12:10 AM
If you have a larger diameter tire the wheel will spin slower at any given speed than the smaller tire. Too take this to extremes, imagine your little 13" trailer tire spinning like crazy at 75mph while your jacked up Ford pickup with monster tires fairly pokes around at 75mph (but humming like crazy, but that is another problem).
Same speed, different rpm's.
The ABS sensor only see's the rpm's. In the software that converts that rpm to mph a few things are assumed to be constant like the tire diameter and the speed will be incorrect if the assumed figure does not match reality.
Same speed, different rpm's.
The ABS sensor only see's the rpm's. In the software that converts that rpm to mph a few things are assumed to be constant like the tire diameter and the speed will be incorrect if the assumed figure does not match reality.