While the Step-Up is skinnier side to side, from the horn/front of the saddle/seat it was exactly the same length as my OEM Road King seat. That being said, the Step-Up moves you up a bit (vertically, not forward towards the tank) by a half inch to an inch (I can't remember offhand). I did a youtube vid with all the measurements (sorry, I can't remember them offhand), I can post a link if you like. I did a walk around vid recently I can also post.

I'm just a tick over 6' & 168lbs with average leg length & it fit me fine. I have a bad back too, that little bit of support helps out quite a bit. They make a long leg version of the Step-Up if you need more room. If you can, try out seats on other people's bikes you know (friends/family) or maybe there's some forum members in GA that you could meet up with & try some options out.

As previously mentioned, rear shocks can make a big difference. My RK has 3" of travel while your RGS only has 2" from what I remember. Just that 1" makes a big difference. Also, check what your stock suspension pre-load is set at. My RK was set at 10 when I checked. Being 170ish lbs, I set it to 0. It's a much better ride. It looks like you'd be at 2 or 3 unless you're carrying a bit more extra weight.

You should be able to find this pre-load chart in your owners manual (it was on page 90) but I'll post a pic anyways.

 

I am 6’1” on my 07 FLHTC I have a Mustang Super tour backrest and Ohlins shocks and 12” Yafee classic apes
on my 14 Tri Glide have a Ultimate Tallboy with adjustable backrest and Pro Action shock and 2+2 bars
See the trend.

 

I can’t afford a Russell or any of the other great Iron Butt seats out there, but using one of those sheepskin / memory foam pads on top of my stock Road Glide seat has made a huge difference.
I also love my backrest.

 

If you’re solo a Corbin with the backrest is the only way to go

 

Alaska Sheepskin Butt Pad. It's that little bit of extra cushioning.... extra breathability.... extra traction.... extra comfort. Personally I would advise anyone to try it on their current seat before risking many hundreds of dollars on the next butt-gamble. We like ours so much I guarantee we will use it on any seat in the future just for its breathable nature and that extra 10% cushion. We bought separate rider and passenger butt pads and prefer the sheared version to the shaggy pelt. I'm also 100% for the backrest, as it makes a big difference for me on longer rides.

As for a particular seat working best for you, that would be like me recommending the right woman. Try a few before you find the right one.

 

A suspension upgrade really helps. Progressive 944's are now on my bike and there are others many recommend. I swapped seats to the Saddlemen Road Sofa with a backrest and it also helped. As was suggested above, go try a few different seats. Good luck.

 

A big +1 to this. IMHO, the number 1 upgrade you can do to your bike is the suspension (including forks). Last month I bought a 2022 RG 107, which has the same seat as the Special. The very first thing I did to the bike was get new shocks. I bought RWD RS-1 13" shocks ($1k) which have 4" of travel and preload and dual compression adjustment. The stock shocks have 2.1" of travel, which is terrible. The RWD's offer a massive improvement in neutering the shock impact of road imperfections, as well as providing more confidence in turning. I'm still tweeking the settings, but I'm pretty much dialed in, and the experience of riding the bike is greatly more enjoyable now.

If you decide to get new shocks, I'd highly recommended Bitubuo 13" Twin Adjustables, which run about $550, as the lowest cost best value entry. Then move up from there if your budget allows. Lots of great option from Ohlins, Legends, ProAction, etc. I'd highly recommend the 13" vs 12" length of the stock shocks though, as they will allow considerably more travel that stock. Better shocks will have more adjustability for preload, rebound and compression, most will have preload and either rebound or compression. If you can find them and swing the cost, the HD SE Ohlins and Ohlins 044 kits are top notch but $1500.

Shocks will massively transform your ride, and alleviate much of what you're experiencing with back pain.

As for seats......

I'm also on a seat quest for my RG. On my last bike, I went through 4 seats and learned, the number one criteria for me, is how does the seat reposition the rider? Does it move you up/down and fore/aft and how many inches. I'm 5' 11" with 34" inseam. For me, being a little taller and rearward is what I'm seeking. I like my legs at closer to a 90 degree angle with knees below the hips when riding, over being really feet forward. If my knees are in line with, or above my hips, I get a wee bit sore from that riding position. A taller seat is the only way I can get there. Then it's a matter of build quality, features and materials. Leaning towards the Saddleman Road Sofa or Le Pera Maverick DLT (daddy long legs tall). Whatever I go with will be the starting point for overall ergos to include a new handlebar and windscreen.

Good luck!

 

So for me anything under 250-300 miles i leave on my lepera. Long trip i throw on the hd hammock. But again what helped me the most was the bars.

 

thats funny because on the wing sites the say that about harleys. ive been on wings and im not all about that feet under your butt locked into one position thing.

ive got an adjustable hd backrest listed in the classifieds section since thats been brought up a few times.

 

I know what you mean I’ve had 3 back surgeries , I have a Ultimate and a Corbin both have a different ride