Hey, is there something that can translate and pdf to an text, so I can use rikai-chan?
Cause in a few month I want to start reading novels, but without rikai-chan I'm sure I couldn't do it.

If it's a scan (likely), you can't. Your only option is OCR (Optical Character Recognition). This works with limited accuracy. You can do the entire book as a batch and use it with Rikaichan or any other popup dictionary reader (but you'll still need the source material as a reference in case of OCR errors), or use an on-the-fly OCR program like KanjiTomo (and there's also OCR Manga Reader for Android). On-the-fly is easier and my preference in most cases, thanks to the quality of KanjiTomo.

Remember that a lot of us learned Japanese before rikai-chan existed, so it's possible.

Thanks Savii, i'll try it out when I get my hands on the first novel.

yudantaiteki yeah it is possible, but why not use something to speed up the learning? The less time I have to spent to identify the word, the more I can spent to learn it.