It depends on your audience. If your audience is the touring community, CBOAB is the most likely place for touring folks seeking journals to look. They are more likely to find your journal there than anywhere else IMO.

If your target audience is not the touring community that is less true and a blog site or your own web page may be a better option.

Do I remember correctly that your ride is a charity ride? If so is there any chance the charity might host your story on their page?