The HSPIN Good & Evil 4 came stock with a 5 mm wide bearing. Most people had a hard time getting a decent bind on it and swapped it for a 4 mm bearing. The later Save Deth issue came stock with a 4 mm bearing.
Yes, for a gap over 6.2 mm you need at least a T9 string.
Way I would to this, put like 10 drops of lube in the bearing, and play.
Set my Dang2 up with a really fat string and three drops of YYJ thick lube. It’s solidly semi-responsive, but this yoyo’s walls are too low to do stalls easily. After it stalls it simply tips over out of the mount.
Double wrapping the bearing makes the response a bit better.