It is impossible not to get estrogenic side effects with Dbol only cycle without the proper ancillaries, since it aromatizes into estrogen. Therefore, the estrogen levels will surely rise, and the only thing that will vary, are the side effects that will occur. Remember, not all of the estrogenic side effects are visible with bare eye, and many don't pay due attentiont to certain side effects. For instance, you can see a ton of bodybuilders with gyno, and they don't even think they have a problem. Therefore, you must always go in the safe way, and use an AI in order to control estrogen levels. Otherwise, you will definitely have problems, be it short term, or long term. Believe you me - it is not cool to suffer estrogenic side effects.