I've been riding for almost 40 years and never understood the reasoning behind a Ironbutt ride. To get on the interstate and blast for 500 miles @ 80 miles an hour in one direction just to stop someplace and nap for 8 hours before turning around and blasting back. Kinda like takin' a gun to the range and runnin' a thousand rounds thru it, just shootin' at the berm. I always figured it must be the patch and the license plate bracket that makes it worth while. Around here, it seems to be an ego thing with BMW riders.......coupla them from town here do it every year........then hardly put another thousand miles on all summer.
50 years ago, doin' it on a rigid frame would be quite an accomplishment, but nowadays, even me with my fatass, with the ol' lady on the back, with the R.K. loaded down like a pack mule, can ride from 7 in the morning till 11 at night while only stopping for gas, Red Bull and Snicker bars. Then we get up the next morning and do it all again. Not a big deal. Difference is, we're enjoying the ride, seeing America from the seat of the bike, and gettin some kewl pics while we're at it.....and altho we never make it a thousand miles, we have done 800 several times. To me, miles in a day mean very little compared to quality hours in the saddle.
But this is my opinion....if it trips your trigger, go for it. Yep, three IBs every four hours, lots of water and keep yourself covered as much as possible. Wind @ 80mph will suck a lot of moisture and energy outta exposed skin, leading to dehydration and mild hypothermia. This can tend to make you confused and slow at reacting and make you tire quicker.
