roll center

I was curious as to how you find roll center or anything related to handling on a tri-four link or a parallel four link, I have finding a decent instant center down pretty well, just wondering about the handling aspect now, thanks for the help!

I might be able to help on this. If you take your measurements of your pivot points and transfer them to a piece of paper. then draw lines from one pivot of the bar through the other pivot forward. Then you will need to do the same for the other bar ( this is in a side view) your instant center is where the to bars (lines) cross. Now on front suspension I have drawings to show how they are done. Max might be able to shed a little more light on it from here. But that is where to start from.

On a triangulated 4-link the simple way to find it is to extend your imaginary lines through the triangulated bars and where they meet is your rool center. On a parallel 4-link, you would look to your lateral limiting device (pannard bar, watts-link...). On a pannard bar, where the bar crosses the center of the rearend is the roll center height. On a watts-link, the center of the pivot is the roll center. It's not perfectly accurate, but knowing exaclty where your roll center is isn't all that helpful when tuning unless you can move it up and down.