Check the upper and lower trees for hairline cracks, and the steering stem to see if it may have been bent. Check the fork tubes for kinks in the tubing where the trees clamp to them. When I got my bike, the P.O. said that he had rear-ended a car, but "everything" was replaced..yeah, right. The steering stem was bent at the lower bearing, and the bearing race was cracked too.
Before you try to get everything back in alignment, be sure that you loosen ALL the bolts and wedge something in the slit to release the forks, and loosen the steering stem nut and jam nut to releive any stresses that the impact had caused. Don't be tempted to force anything back to straight.