I used heat shrink as well. I would think that heat shrink would do a better job and last a lot longer than duct tape. With the heat shrink I used it took 3 or 4 layers to reach the recommended thickness.I cut my tubing at 30mm or so in length. Heat shrink tubing also shrinks a small amount length wise. So if you start with 22mm it will be less than that after it is shrunk.After I shrunk the tubing onto the shaft, I cut it to length. I simply rolled the shaft on the bench to cut the tubing square with a razor blade. I cut the first end nice and square, marked the other end at 22mm, then cut it.I don't have any pictures, but it's rather simple. You need to end up with a 22mm length of tubing in the center of the feathering shaft. you layer enough tubing to get as close as possible to, but not over 11.65mm in diameter. The tubing rides in the center of your headblock, tight between the dampeners.Don't come off the throttle untill you see your GOD!