One of the most frequently heard statements, or comments, from those riding big touring Harleys or other brands altogether, is that sportsters (and especially the 883 series) are only sound for short downtown spinning. While it is true that they are small, light and may not carry two heavy-weight persons comfortably, I have to disagree with the claim. My bike is a XL883C, with forward controls and 883 cubic centimeters engine displacement.
What I do agree with, is that extreme distances with a long-legged or well-eaten passenger may feel a bit cumbersome when riding a sportster. That is because the wheelbase and back seat passenger area are a bit shorter than on Big Twins. Not because the 883 CC engine would be underpowered, which it is not. And, lets face it, stock suspension in sportsters seldom is enough for comfortable two-up riding.
But, when doing LDR solo, things are very different from two-up. The 883 CC engine is very well able to make quick and safe passes from cages, and while its acceleration may not be the eighth wonder of the World, it has plenty of low-RPM torque. It can haul your bottom and your belongings with comfortably low RPMs, up until to the 120-130 kilometer per hour range. It will go faster, sure, if the rider is able to bear the increased wind resistance on his/her body for extended periods.
My longest 24h rides have been around 1500-1600 kilometers, or 900-1000 miles, with stock seat and stock suspension, and D&D exhaust (not the quietest around). Now while I could feel the ride on my back and on my bottom, there wasn't anything that couldn't really be done. I think attitude has a big role to play when doing LDR, if you prefer comfort you need to buy a really expensive luxury cruiser. Take a short break every 80-100 miles and you´ll be fine with a sportster.
One thing that could be better, other than stock suspension, is the standard lightning. Even if new models have very bright headlights, it is still just one light. Every time when riding at night and it is raining, I swear to buy a set of auxiliary lightning. Riding with just the standard lights at night can slow the riders average speed, which can be a problem during Iron Butt rides.
Many people have had to change the stock seat to something else, like to the Sundowner seat etc. Apparently I am lucky because I can sit at the stock seat all day. I guess they have made the stock seat a kind of a compromise, one size fits all, which of course it doesn't do.
Big cruisers have lots of space on hard saddle bags to stuff up all your favourite camping equipment. Sportsters have none in the stock configuration. There are lots of cheap saddle bags under $100 or EUR100, and you dont absolutely need then, just take the biggest rucksag you can find, fill it up and tie it to the back seat against the sissy bar. There, you also have a nice backrest.
Custom models, XL883C and XL1200C have 4 gallons or 17 litres gas tank, which is good for touring purposes. You can get over 300 kilometers or 200 miles from it. Those models with the 3.3 gallon peanut tank may be a little limited as far as operating range is considered. If you have the 3.3 gallon tank, you may be well advised to buy a small 1 gallon gas can and tie it up somewhere on your ride. I personally keep 5 litres gas can with me if I ride somewhere far, just for the added peace of mind.
People have been doing long rides, Iron Butt etc, with much smaller and slower bikes, two-up included. if it can be done with 125 CC and 10 horsepowers, surely it can be done with 883 CC and 49 horsepowers. Maybe those commenting (jokes aside) just are too comfortably oriented, wanting their nice Big Twins with windshields, heated everything and a coffee maker. A coffee maker... Truth be told, a saddlebag-integrated 12V coffee maker _would_ be cool. Well, I DO use a navigator, and I DO have a 12V accessory outlet.