Well, I've done a wee bit of off-roading in Normandy on the Uly over the weekend
When I bought the X recently, I inherited the following tyres;
Front: Dunlop D616, hardly worn
Rear: Dunlop Roadsmart, more than 50% worn
As the rear is purely road-biased, I was expecting a bit of trouble but we took a couple of fairly easy trails. There were short sections of mud and some rocky (not loose) bits. No bother at all, as it happens
.
I was in the company of more 'serious' enduros (XTZ1000 and R1200GSA) which were also shod with road tyres. It seemed to me that the weight and balance of the Ulysses made up for any shortcomings associated with a wider rim and 17" front. The suspension travel is OK so my only concern is the crash-resistance if I drop it
(no crash bars available).
Jon