Select the first link then go to animate/graph editor, with the graph editor open select the curve in the graph edit and go to tangents/spline..............dave

I think I know what the problem is but I did know how to fix it till I came across this link.............dave

http://forums.cgsociety.org/archive/index.php/t-1048324.html

Did you rebuild the curve like Rick said?.................dave

A useful tool to know, I used this on my tank tread........well done Rick...........dave