I've got a minute, so I'd like to elaborate on why I hate the hex-bar, and what I did in pursuit of making it hex-bar work before I just went to sync-link.
The first problem, the one everybody thinks is the only problem, is the ball-joint and spring set-up on the ends. The heim-joint/bearing fix is touted as being the do-all/end-all, but all it does is fix one of four actual issues.
The second problem is with the heim-joints on the drop-arms. At best, they are exposed to crud and dirt, and require lubrication to stay limber. At worst, they are tight, and sticky. I've had more bad joints that good-- I have at least 20 rods of various length with "good" and "no good" ends on them. The "good" ones are pretty iffy. 80+% of them are "no good"
The third and fourth problems are with the actuator arms. The hex cuts in the arms are not always oriented the same, arm to arm. If they aren't, you're screwed-- the geometry side to side won't and can't be identical. It's good to have a stack of them, so you can flip them backward and see how they meet up in the middle. If you get two arms that are the same and again, I've got a stack of about 10-- you still will have holes for the drop-link heims that aren't lined up. I would get a matching set of arms, fill both holes with JB Weld, and re-drill both of them to get the geometry identical.
After all that- picking through a stack of parts to get arms that match, heims that are limber, drilling new holes in the arms, and doing the heim-joint modification on the supports for the hex, I had something that worked. For about a year.
Eventually the axles on the heim-joint modifications (on the ends) wear down and give you slop. Invariably, one drop-link heim would lock up at the worst possible moment. In the end, I just lost the will to make something so incredibly cobbled together work right.
Lots of guys have them, can't make them work, then blame the carbs. I've often said that 90% of carb problems are ignition. Of the remaining 10%, at least half are linkage. You really don't have to live with that.
Forewarned is forearmed.