the dax rush i had had huge 255x40x15 tyres on the back and the track was if i remember right about 50mm or more wider EACH SIDE than the front. there was no handling problems with it at all - the only thing that you really have to watch for is remembering you have a wider rear end than the front! reason - your blasting along a country road - in this instant kirkstone pass in the lakes - narrow road - car comes other way - you gotta squeeze over to the left a bit - the front wheels miss the big rocks on the left but does the rear? naaaaa of course not - it can stop the car dead from moving..
so iv heard.. baaaaaah...