Should it be pretty easy to rotate your spring to set the sag? I have watched some videos online and they are able to spin it pretty easily. I have the top collar all the way loose and still have to smack the bottom collar fairly hard with a hammer and punch.
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it really depends on a few things. How far is the spring compressed, are the threads clean, are the threads damaged ect. I usually am able to tighten mine on my yz by hand by using both hands. I use my right hand to turn the spring itself, and my left hand to turn the ring. I also find it easier to tighten the spring, rather than loosing it.