A folding rotor blade assembly for a tiltrotor aircraft comprising a rotor blade pivotally connected to a grip with dual concentric blade bolts having a common central axis providing a pivotal axis inboard of an outboard bearing. A folding spindle connects the outboard bearing to an outboard tip of a yoke. The outboard bearing and the spindle fold with the rotor blade relative to the yoke. In use, the compact folded arrangement of the rotor blades reduces folded aircraft dimensions in response to ever increasing restricted storage space parameters.