The first thing you want to do is reinforce the Hammock seat's sling retainer. This thread will explain that: https://www.hdforums.com/forum/new-r...eat-sling.html

As far as the backrest mount goes it needs to be installed so that it aligns properly with the opening between the riders and passengers seating positions. Neither my wife nor I are exactly lightweights and we both have plenty of room.

 

First off I am a firm believer in the Hammock Seat. I had the pre 14 version on my 2009 Road King and moved the seat to my 2016 Road Glide Ultra when I purchased it. My 16 Ultra was totaled last September.

I just purchased it's replacement two weeks ago (2018 Road Glide Ultra) and before it rolled out the door it hand the current model Hammock seat on it.

I decide to put a backrest on the 2016 FLTRU, got all the parts and completed the install. No mater the adjustment the back rest was pushing me forward out of the pocket of the seat. I did some pretty extensive modification to the adjustable mount which included modifying it to move it 3/4 of an inch further back and changing the supports to increase the angle to allow for more lean back adjust ability. I finely got it to fit me on the bike perfectly and even had a little tilt back room to spare.

Everything was great! also long as you were on very smooth roads Which we have very few of in South East Texas.

The problem is what makes the seat so good itself. When you get on a regular seat the foam compresses to a point to match your weight and everything stays at that point the seat and the backrest stay pretty much at the same points. However, With the Hammock it is never fully compressed it allows movement to absorb road shock and bump that the suspension doesn't suppress. So, While your moving up and down in the seats suspension the back rest is staying stationary. The seat actually has a couple of inches travel and as stated before the back rest doesn't.

Everything seems fine for the first 30 min to hour but after that the back rest starts taking it toll. Again this is very dependent on the smoothness of the roads you ride.

Disclaimer! My Experience is with the 2009 thru 2013 Enforcer seat. The new seat is suppose to be different in some way from the earlier version and I don't know what the differences are .
However, due to the way the seat works I don't see how any changes to the seat would correct the fixed back rest issue I experienced.

I am perfectly happy with the Hammock seat without the back rest. If need should ever arise that I need a more comfortable seat I will probable get a Day Long Touring Seat which is suppose to be the best there is, But there so dam ugly!!

 

I would suggest a suspension upgrade. New properly damped and sprung rear shocks will make a world of difference.

 

I found that the 13 down hammock is considerably more comfortable than the 14 up models. So much so, I put the older one on my Rushmore TK. It gives you a little more legroom also. To make the adjustable backrest work and fit through the seat slot, I shimmed the 2 lower bracket bolts which tilted the backrest arm further back.

 

I've run 4 different Hammocks over the past few years as well as HD, HD Adjustable, and Mustang Backrests.

Best setup I had was the older version Hammock (it's a tad wider in the seat) with the Mustang Backrest.