Did you put one bolt in your bar at the point where you wanted the stiffness set or did you put bolts in ever hole to set your stiffness? I just noticed in this pic from their web site that it has bolts in every hole.

 

I only use one also but it can't hurt to use multiple bolts.

 

You are supposed to use one bolt. You could use more if you want to.

 

Might even help prevent the cracking that the v.1 bar was prone to see.

 

Its kinda small, but I only see the bolt in one hole in that pic - the bungs welded in the tube protrude a good bit outside the bar so it looks like there are bolts, but I can only really see the bolt in the 2nd hole from the passenger side.

At any rate, I only use one bolt, but I have one of the latest versions of the bar as well.