if the adjustables are already on your car, no you do not need to take the wheel off. but taking the wheels off will make it a whole lot easier.
and the ads of the guy adjusting them with one hand is BS.
you will need to loosen the collar with the allen key provided. then with you turn the collar how many times you want. keep count of it. when done, tighten the collar with the allen key...and you are done.
takes a good 5 mins for each wheel.
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