You need some short valve stems to turn your wheels around, otherwise it will hit your brake caliper on ever rotation. As far as the bump steer and the extra pressure on your spindles, they are both myths. First, you are moving your wheel out, not changing any of your steering geometry, so there will be no change in the way your wheels turn from they way they would be turned in. In case you dont believe me think about this, Douglas sells rims with an offset that is the same as turning you wheels around, if this effencted handeling in a negative way, you think they would be selling them? Okay, as far as the spindles, absolutly no effect, the only diffence is the weight that the inside and outside weight distribution will be a little different, same amount of weight, same forces since you really arent moving the wheel in reference to the spindle very much. The bigger force change will be on your upper and lower ball joints, since they will now be 2 inches farther away from the center of the wheel, there will be 2" more leverage of weight applied to each of them. I really doubt that will be an issue.

 

I have ran then wheels flipped in also for years and no problems found. You can take out your factory valve stem and turn it to the inside and just drill a new hole on the other side and put in the new stem the correct way, that way you can air up your tires easier. just a thought!