Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
My Garelick mount has a heavy duty metal bar/strap that locks it in the up position. The strap is bolted to one side of the mount, and you sort of pop the other end over one of the other bolts making a triangular arrangement. I don't completely trust it even though it's never come loose on the road. I crank down the locking nuts on either side of mount for added security.
With my old OB which was mounted to the transom, I mostly made sure the cowling was securely attached so it wouldn't blow off at freeway speeds.
I make sure the motor and mount has extra support. I tie a rope to the cleats, to the motor, and mount. Then I make sure to go slow/easy over bumps and such.
We've trailered thousands of miles with the OB mounted. The highways are less stressful on the OB and boat than a rough day on the water. Maybe Jim Sweet (Sweetcraft) will chime in. He built a neat support that provides additional support for his Honda on his C25.
OK here is a thread with Jim's support system. Alas, the photo has shrunk but you can still see the setup.
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ. The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.