If you think a loud pipe will warn cars that you're coming, science says otherwise. I just wrote this article for Autoweek. There's a link to a video detailing the study.
https://www.autoweek.com/news/industry-news/a35952569/loud-pipes-do-not-save-lives/
Yes, it's true, I work at a car magazine, but occasionally they let me out of the box to ride motorcycles. Here are some nice ADV bikes, all wrapped up in a single article: https://www.autoweek.com/car-life/a35718882/10-coolest-adventure-bikes/