I have to pull some low voltage Belden cable (4 twisted pairs) for alarms on my generator installs. We run 1/2 pvc conduit, never more than 3 90s and it is the only thing in that pipe, but it is the hardest pulling stuff I have ever dealt with if you try to pull it dry. Just a squirt of Clearglide lube makes all the difference. Must be the jacket that makes it pull so mean without lube
