Take a look at the video Buggyman shot of his CVTs cycling through their range on his big Max II. http://www.6x6world.com/forums/transmissions/25160-cvt-test-run.html
The drive belt should run all the way up the shoulder on the primary clutch when the vehicle reaches top speed. If you can't safely watch it while driving, take a black marker and draw a line on one of the drive clutch sheaves from the top of the belt to the outside of the clutch. The belt will wear away the marker (or at least some of it) during its cycling. If you still have a lot of line on the clutch sheave after a test drive, it's likely that the drive clutch is restricted in some way. If you're only running 2 out of 3 rollers for example, the clutch won't cycle through its range.