Originally Posted by thematt
It takes longer to fill a tank from rotopax than it does from a gas pump, time wise. And iron butt rides, in order to get that many miles in one day, are mostly road rides - which have gas stations. There's just no need to carry that much gas (even the TT tank is overkill) when you are on regular roads.
There was a mass Iron Butt ride with >1000 miles on dirt roads - it can be done (haven't done it myself).
For road rides - each gas stop costs you 10+ minutes from the time you exit the freeway until you're back up on the freeway. If you try to cover 1500+ miles in less than 24 hours one way to do that is DO NOT STOP FOR GAS. It doesn't mean it cannot be done (I had to stop every 180 miles with the GL1800) but it saves effort and time - which is improtant.
There are VERY few that try the Iron Butt Rally with a stock tank that only gets you 200 miles. However the above would be illegal as all fuel must be in a tank (not rotopax cells strapped to the bike) and the toal is 11.5 gallons in total (unless you ride a trike).