I had the same question. Doug
I had the same question. Doug Burton answered this for me a few weeks ago when I contacted him directly. Here is his response:
"Since the redesign of the upper front tube pivot yoke, the safety bolt doesn't play as much of a role as it once did. The tube clearances are tighter, such that there's enough friction to keep the halves from parting if you leave the clamp loose. But don't leave it loose
If you'd like to use a safety bolt, looks like you'll need a longer one of the same thread, probably about 20 - 25mm long."
Hope that helps.
Mark