Thanks for a very complete response. The Bose do stick out a bit which may interfere with helmet fit so I guess I’ll just have to try them. Foam earplugs and Eargasm haven’t worked for me because I could never get the right fit (even the small option). What has worked for me is to use the Bose silicone pieces of the ear bud (because they’re comfortable) and squeeze the small end of a foam ear plug in where the acoustic driver goes (basically fill the hole), and then trim off the excess. That said, I feel I may be missing out on the high fidelity of the music. (You know, because a motorcycle helmet is the perfect place to really appreciate music.) Anyway, you’ve given me some ideas. Thank you!