You only need the proper socket wrench to tighten them. But make absolutely sure you use the proper washers behind the bolt heads. A touch of grease on the backside of the washer helps.
EDIT: and others will undoubtedly disagree with this but: clean the tapers in the crank arms and the spindle flats very well,
with alcohol or similar, and do not lubricate either of them when installing.
Last edited by rootboy; 04-21-13 at 10:38 AM.