The Memory of Running by Ron McLarty
Smithy Ide doesn't have it easy. He's 279 pounds, 43, a smoker, and drinks too much. He's stuck in a boring, dead-end job in Rhode Island. He has no social life. And then he loses his parents the same week he discovers his beloved but insane sister's body lies unclaimed in a morgue in Los Angeles. While drunk, he starts to clean out his childhood home, finds his childhood Raleigh bicycle, on a lark decides to coast on it to the end of the driveway, and..... well, I won't go further with details. I want you to read this warm-hearted novel, and not just because it's a tale well-told.
One of the themes the author plays in the book is something that anyone who has worked to lose a lot of weight will recognize. The Memory of Running is what might be called a "travel novel", meaning a work in which the protagonist embarks on a journey physical and spiritual. The author makes this point by emphasizing that Smithy is on a "quest." Both Twain's Huck Finn and Voltaire's Candide, two other quest-followers, come to mind as distant cousins of Smithy; indeed, Candide and Smithy share empty-headedness as a feature of their personalities. However, unlike Huck and Candide, McLarty's hero is trying to work out his physical problems. And like many people who lose weight, Smithy, as he travels and his weight changes, grows as a person. Often fat people, trapped by their girth and their lifestyle, live the life of passive despair that Smithy 'enjoys' at the start of the book. McLarty's use of this 'weight loss trope' is subtle; he's helped here by having the clueless Smithy narrate the book.
Finally, the bicycling references in the book are modest; the bike serves as escape, transportation from Smithy's past and present, and as a symbol of that past. But the book's not about the bike. Nor is it about weight loss. But anyone who is fond of bicycling or has at some time had a problem with obesity will find this novel entertaining.