I didn’t like the stock muffler clamp that came with my engine kit so I made a clamp from a short length of ½” dia. aluminum tubing and two stainless steel aviation clamps. I cut the tubing length to fit the space between the down tube of the bike and the muffler, and then cut slots on each side of the tubing for the clamps to pass through. I cut the slots for each clamp on a slightly different alignment to account for the difference in alignment of the down tube and muffler (they’re parallel in one plane, but not another). See the attached photos for what it looks like. It’s much more secure than the stock clamp.
