I wouldn't get half expected 4-5000 mileage on vintage or modern rear w/o straining leans wearing tread down on either side of center. I absolutely hate/fear the wide balloon tires when they get near edge its like stepping off cliff edge upsetting compared to vintage stiff sticking >>> IF vintage fitted on *too narrow* a rim going by the manufactures' legal department guidance. Must take fouling things off a factory C'do or lift its suspension to get over on tire edges at speed though as the G force tends to sag springs lower. 120 size/wt tire on a normal mass and power Combat feels like running in work boots, but if power/wt ratio to be concerned with tire spin leaned, a 120 on WM3 rim stuffed in is my favorite sports biker embarrassing rear, *on linked tamed* isolatics or might learn more than ya want to about rubber baby buggy HInge. Switching to radial tires led to need of stiffer frame designs. Much as www and general un-experienced published opinions warn about mixing radial and bias, BMW sold a bunch of em like that in 80's w/o problems and I've done it on my SV650 a lot to only notice the radial don't tend to climb road crowns as much as bias so I tend to like radial front and bias rear on my balloon tire modern. Some where between 130 and 150 size rears lies the difference to me between skinny tires that keep edge profile predictably long and narrow vs walking around a couple inches on deforming shortening balloon tire patches. You may find radials more compliant side walls raises isolation threshold some compared to stiffer bias tires. If mix/match radial and bias tires, air pressure balancing needs a bit of experimenting to get the handling more predicable.
