Rear tire wear

On my 2013 goldwing with a roadsmith kit rear tire cupped on the inside. Been running 25 psi. Had 16000 miles on the bike. Left on a trip last thursday, developed a vibration at 65 mph and up. Had to put new tires on in Jamestown ND. Looks like the tires ride on the inner side of the tread, more than the out side . Can you adjust the tilt of the rear tir

Just asking here but isn't 25 lbs. just a tad to low for those rears?? That alone could be the reason for fast tire wear??

Ronnie

PS: I'm not a tire guy/so just asking a question here only (no expert)

Ronnie

Road Smith recommends a minimum of 26 lbs.

Barney