[MrBasse]

Those bolts are good, but they will bend, our Logomotion bot bent all 6 and then 6 more in one season... and it only weighed 84 pounds.

The biggest issue, is that once they bend they are incredibly difficult to remove for replacement. Ours bent to the point where they caused our wheels to wobble and started throwing chains. We use grade 8 bolts now and have had no problems.