I've built a quad recumbent. (http://quadrecumbent.blogspot.com) I'm looking for a way to control both rear deraileurs from one shifter. I've kicked around a couple of ideas like a slide control with the cables connected to it or a cam type device. I'm currently using the shift control for the left side from the right hand on the left bike. The problem is the shifting pattern is backwards and its difficult to remember some times that the left side goes the opposite way. Any ideas are extremely helpful.