02-16-2023, 01:55 AM
A 8" long 1/2" drill bit worked well on both Sportsters and first Bonneville, however, after drilling 4 holes (1/2") under the CB1100 muffler cover, I liked the sound at idle, but not accelerating or cruising; so the holes were covered with plates, attached by screws (drilled and tapped) to return to stock. So, if drilling is decided, you may want to figure out how to return to stock, if sound is not as desired.
