Whether or not you put a bounty on your question is entirely up to you.
Just do a little cost-benefit analysis:
Which is more important to you: your reputation score, and increasing it as quickly as you can to get the next privilege, or getting a complete answer to your question as soon as possible.
I usually sit on mine for a while before offering a bounty (I like it when my questions are answered just because they're good questions, and not because I put a bounty on them), but that's my personal preference and honestly is fairly irrational. But it makes me feel good about my puzzles :)
Do whatever makes you happier.
Good luck and happy puzzling!