Hi Greg,
Thanks, yes, the distance between the side of the main drive pinion and the front side of the dog ring. I put a 0.1mm shim between the front snap ring and the bearing and it get rid of the slop. I just can' imagine there should be much gap since it allows the dog ring to kind of tilt. There's probably about 300 passes on this trans and yes, slipper clutch. My last Jerico lasted me about 2000 passes before it grenaded and I but it used.