maybe you can help me with this one. i have a surly steamroller that i ride everywhere. recently when going off of a curb a loud "chank!" or "chack!" or "chunk!" sound came from the front wheelish (maybe headset) area. i thought i cracked my frame. i inspected everything and i couldn't find any cracks anywhere. then i started to bounce the front wheel off the ground to see if i could replicate it. every forth of fifth bounce or so i could make it do it again. it's a loud sound and it's sort of discouraging. i want to fix it.