My advisor wants to co-author a paper on my thesis work, but drags out the submission, claiming it isn't ready. Should I submit without him? I have just finished my PhD thesis defense in applied mathematics. My supervisor suggested me the initial problem. He was not an expert in the small area that I was working, and thus the assistance from he was minimal. As we had so many disagreements in the research direction, our relationship was rather uncomfortable. The good thing was that I finally got the problem solved, with assistance from some external experts. 

After I finishing my PhD, I extracted a paper from my thesis. My supervisor insisted that he should be authored as we had discussion on most of the result, and if I submitted without his name, he would appeal to the journal editor. But on the other hand, he deliberately holds on to my paper. He keeps on saying the paper is not clear and is thus not ready for submission, but there is no revision comments from him for several months. 

Should I submit the paper alone with only name? It seems each side is highly risky for me.
The first things that jump out at me from this question are these: 


Why do you think that your advisor is dragging his feet?
Why do you think your advisor is incorrect about your paper not being clear?
What is the time schedule on which you expect to publish?


Now, this may in fact be the case, but in my experience, in most cases even graduating Ph.D. students are not very good at writing effective scientific papers.  Your writing here does not argue you are particularly different: I am not speaking of grammar (which is relatively minor), but the fact that you have made strong assertions without presenting supporting information or giving key pieces of contextual information.

I would thus guess, a priori, that your paper is indeed unclear and not yet ready for submission.  Moreover, I would guess that your frustration is coming not from your advisor "dragging feet," but from you feeling unclear on what steps you need to take in order to edit your paper into a state that he finds satisfactory.

That is what I think you need to address in your plan to move forward.  Focus on one piece of the paper at a time, e.g., start with the abstract and ask for specific and concrete feedback on how it is problematic and how to improve it.  If you can meet regularly with your advisor and start learning the pattern of what is missing and what you need to do to improve it, then you can likely get the paper into a submittable state in a reasonable time.