Yes. You may. As long as you pick it up and put it back down, you may. I can't look at the translation now because the main page is down, but if it says, "You may only use one Poke-Power Speed Gain per turn" then the answer is no. After you use it once, there is no way to repeat it until your next turn in that case.
EDIT: Ninja'd. Just as a side note, there's an easy way to tell with this sort of thing:
Any Poke-Power (like Claydol's for example), that says, "Once during your turn..." but doesn't directly say you can only use that particular Poke-Power once per turn, you can use it again as long as you return that Pokemon to your hand first or have a 2nd one of it in play. Otherwise, unless it's as many times per turn as you like, you may not use the power more than once (Spiritomb for example).