Creating a book of memories is a perfect way to honor a family member on his birthday, particularly if he's sentimental. Commemorate him and the time you've shared together in a photo album or scrapbook. Include all sorts of things, from concert tickets and event stubs to photos and sketches or drawings. Even a poem you wrote for Dad (or one of his favorites written by someone else) would make a good entry.
You can organize the book by breaking it up into different chapters, with each chapter representing a year, event or theme. For example, you can devote a section to Dad and his motorcycle. You can stick pictures, receipts, tire impressions or anything else bike-related into that portion of the book, so there will always be a place your father or anyone else can go to relive the fun times he and the rest of the family had on that bike.