Counter conditioning works best for fearful dogs when used together with desensitization and involves putting the object he is fearful of together with an activity or behavior he recognizes as pleasurable to divert his focus.
How to Use Counter Conditioning
Using a bicycle as an example, if he is fearful of a moving bicycle ask the dog to remain in the "sit" position.
Using the desensitization technique, while your dog is exposed to the object he fears, ask him to perform some obedience exercises, such as "sit" and "down."
Reward him for obeying and continue to have him obey commands as the object is moved closer to him.
If your dog doesn't know any commands, teach him a few using treats and praise.
Don't ever use punishment on fearful dogs, collar corrections, or scolding to teach him the commands, the purpose of this exercise is to associate pleasant things with the stimulus that now frightens him, giving him a distraction.