I have seen several police motor's, as well as civilian models with aftermarket risers such as yours, develop a lot of "wiggle" or "slop" in the bars. A lot of folks seem to think "it's normal, they all do it". However, what I have found is that the rubber bushing tears, cracks, and starts opening up a gap between the collar and the rubber where it is pressed into the upper triple tree, this MAY be the wiggle that you are feeling. Yes, with the taller, further to the rear leverage, they will move more than the stock set up, but if you can move them up and down more than a little, you may want to check the bushing for damage. They can not be tightened, as they are a shouldered bolt, with a limited amount of threads, and trying to tighten them will do no good if they are starting to show signs of damage. The only repair (to actual damaged ones) is to remove the upper triple tree and replace it.
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