I took one too many psych courses in college and ended up with a major so take this with a grain of salt. You could try giving your dog treats when he approaches the bikes (pair it with a bicycle ding for the Pavlovian effect!) and get him to sit or lie at it too so that he doesn't feel so negative about it. Maybe this is something to do just so that he doesn't get so violent when you are walking him and a cyclist flies by.