If the book is out of copyright, then sharing it legally might be possible. But if it's under copyright, then I can't recommend free sources. I should check the author's or publisher's website to see if they offer free samples or chapters. Also, maybe the user is referring to a different type of content, like a PDF of a guide or something else related to biking, but the name "The Gentleman Biker" seems like a novel.
Wait, the user specifically said "read online free portable." Maybe they're interested in a free version if it's available. Some authors do offer free chapters or excerpts. Maybe I can check for that. Also, perhaps there's a PDF version available for academic or library use, but again, I need to ensure it's legal.
Alternatively, if the book is not available digitally, perhaps there's a print version that can be borrowed from a library. If the user can't find it, I should explain that and suggest alternatives. Maybe similar books in the same genre. Also, emphasizing the importance of supporting authors by purchasing books or accessing them through legal means.