48"...?
Howdy, Steve -
Are you sure that is a 48" wheel...?
The old YS catalog PDF I found shows 40" to be their largest...? I am no expert, though....
I believe their 1" diameter straight shaft wheels were standard and interchangeable.
Current Edson replacements are made in both 3/4" and 1" diameter hubs in either straight or tapered shafts.
Funny coincidence...I have a 36" YS on my E38 and was casually looking for a 40" wheel.
Please let me know if you would be interested in figuring out some kind of swap. Shipping may be prohibitive though.....
Sometimes the Marine "Used" chandleries like Minney's Yacht Surplus in Newport Beach, CA have a decent wheel or two...kind of hit and miss....lots of junk to paw through....
Let me know, and best of luck...!!
Curt