GL1800 Fork Springs and Rear Spring by Progressive Suspension:  According to the company Progressive Springs, The GL-1800 fork springs are progressive rate (of course), which translates into a soft initial ride with the springs progressively stiffer as they compress which prevents div­ing and bottoming.  Made from the highest quality materials available, the GL-1 800 fork springs #11-1521 carry a LIFETIME warranty and carries a suggested retail price of $109.95.  A Progressive Rate Spring has the advantage of a rising rate resistance to compression. For example, a 40lb. to 65lb. Progressive Rate Spring will take 40lbs. to compress it the first inch, then 42lbs. the next inch, and so on, until the end of the travel; it will take an additional 65lbs. to compress it the last inch. The benefit of this is that the spring can be soft enough at the start of the travel to offer a "plush" ride yet be firm enough at the end of the travel to soak up the big bumps.  I had my springs installed by my local Honda dealer and feel that either they didn't install them correctly or they didn't use the correct fluid as they were kind of harsh to my tastes.  We also took a trip of 8,000 miles from Colorado to Nova Scotia's Cabot Trail road about a year after having them installed.  The roads in 2003 were in pretty bad shape apparently all across North America or so I thought.  In Virginia, we hit a dip in some small town and lost the spring holding the center stand.  I never really got to see the Cabot Trails scenery as all I could do was swerve around as many pot holes as I could.  Anyway, when we got home, I had found a broken shock seal.  I had the dealer repair that and change the fluid.  They put in a little heavier fluid and told me that I would need to ride with my suspension at or around #25 to avoid the feeling that I could break my teeth when hitting pot holes of any size.  Since I am height impaired, I just had to get used to the ride at a lower setting.  Check out their website by clicking on their link button to the left.

According to Progressive Springs, the new GL-1800 rear spring #01-1179B solves the problem of a too soft spring for the GL-1 800 owners who carry heavy loads and overpower the stock spring. It also carries a LIFE­TIME warranty with a suggested retail price of $89.95. Progressive will also offer a special spring tool for disassembling and assembling the rear spring.  As to this rear spring, I don't carry heavy loads, so I had a friend of mine install them on his bike as he does and could install it himself.  The spring tool, #32-5509 ($49.95), that I obtained from Progressive was very helpful.  He found the instructions, along with the Clymer GL1800 manual made the installation fairly straight forward.   He has found the comments made by Progressive Springs to be very true and he is a happy person.  Check out their website by clicking on their link button to the left.

Progressive Suspension's 450 Series IAS Shock for the GL1500:  As I had recently had their #416-1633 GLA Air shocks installed on my '95 GL1500SE and was in the process of selling it to buy the new GL1800, I had asked John Pacello who lives in California and rides a '93 GL1500SE if he would install this new shock and write a product review for us. The following is his review:

Recently, Progressive Suspension introduced the 450 Series Shock for the GL 1500. The beauty of this new design is, as long as your curbside shock holds air you only have to replace the one shock (left side).
The new 450 series shock is touted as the newest shock technology. It has "Inertia Sensitive Dampening" and a "Progressive Rate Spring". I think I understand, they have a neat little video on their home page to demonstrate it.
I was suspicious of the amount of work my current shock, original equipment, at 68,000 miles was actually accomplishing. Some of the symptoms of catastrophic failure were: on long corners the 1500 frame appeared to have a hinge in the center, like a front-end loader, the under carriage would drag on corners with only the slightest bump, and most important was on a strait line whoop the shock would bottom out then top out and I would hear those immortal words, from Mickey my co-rider, "Slow Down You Fool", and on more than one occasion I receive a severe beating from the thrashing miniature fists of iron. No amount of air pressure helped the ride or healed the pain.
Once I received the 450 shock, I decided Thursday would be the night. I had promised to do this article so against my better judgment I read the installation instructions, not once but twice. You know the usual stuff, place bike on center stand, and turn off engine.
I have removed the saddlebags once before, for no particular reason, just to see. So with this great background of experience, I set out my 3/8" metric sock set, an air butterfly wrench, an air ratchet and the necessary Allen wrench sockets. I removed the seat and saddlebag in short order, I did not disconnect the wiring or the latch cable for the saddlebag door. I left the cable and wiring in tact and swung the bag to the rear and supported it on a plastic container. This made the old spring shock visible.
I then removed the two bolts that go through the upper and lower mounts of the existing shock, with a punch and a hammer tapped the mounts from the clevis and pulled the old shock out, just that easy. The new 450 has a cam adjustment, that goes to the
top. I was able to get the top clevis and bolt installed hand tight, but I was having some difficulty getting the bottom bolt through the lower mount, because of the trailer hitch bracket. The shock appeared too long; there was no room to work because the trailer hitch was in the way. I added some air to the other shock, which forced the swing arm down and presto in went the bolt. I torqued and Loctited the two bolts and swung back the saddlebag, replaced the seat cleaned up, complete!
Friday night was the first test ride, I admit I was apprehensive; we were out with a group of friends for a dinner ride. I was waiting for some comments from the back seat but alas not a word. Finally I asked, "honey" I call her honey, when I am trying to be nice, "do you notice anything different in the ride", I got a real positive response "I think so". Two hours in the garage and I get "I think so".
I need more time to evaluate but after one ride and 1/2 the air pressure, 35 PSI and the shock set on the 3rd notch it is like night and day. Cornering is really positive, no wallowing, no bottoming out, and no wild thrashing from the iron fists, and that's a good thing.
It is the next weekend now, I need to be retired so I can get more riding in, I remembered in the instructions they said it is necessary to adjust the ride height and sag. This is a three-person task. Mickey (1) a measurer (2) and me (3). With the bike on the center stand, a) measure the distance from the axel to a vertical point above the axel on the frame, b) remove from stand and with Mickey and I in position add air so the bike is only 1" to 1-1/2" lower than the un-weighted height. Record this pressure and then do the same thing solo and when you ride double add the air to meet the first test pressure and solo reduce the pressure to meet the second test pressure.
All in all I am very satisfied with the new 450 shock; I now have about 500 miles on 450 and have not bottomed once, not once. The instructions say, "Compliment your new shock with a set of Progressive Suspension fork springs". I guess that is my next project.
The SRP is $395.00.  Check out their website by clicking on their link button to the left.

Progressive Suspension's #416 Series Rear Air Shocks for the GL1500 are essential to give you back the comfort and safety for all road conditions, like it did when your Wing was new. I hadn't given the rear shocks much thought until it felt like the back end was bottoming out. I then arranged with my Honda Dealer to install new Progressive 416 series air shocks in the rear. I had already replaced my front fork springs much earlier. If you have the equipment and ability to do your own work, it isn't all that difficult. If your like me and get hurt easily, have your Honda shop do it for you. Mine charged me 3.18 hours of labor, so that gives you an idea how long it might take you, especially if you take in their expertise and tools, etc. The instructions that come with the air shocks are very good and are not hard to follow. They even tell you how to obtain the proper air pressures to respond comfortably and safely to all road conditions. The instructions explain that you should have the motorcycle on the center stand, preferable with the rear wheel off the ground. Inflate the air adjustable shocks to their maximum. Then take the bike off the center stand and load the motorcycle with the rider, passenger, riding gear, luggage, accessories and trailer if you're going to pull one. Then gradually release the air pressure a tap at a time. The moment the bike begins to let down, that's where you want to stop. If you add or subtract weight from this point, a "ballpark" air pressure recommendation is to increase/decrease air pressure 10 psi for each 50 lbs. of weight variation. The instructions even talk about how trailer tongue weight or accessories mounted behind the rear axle may require slightly more that the 10-psi per 50 lbs recommended ratio due to the weight being behind the axle. This is important information to know in order to achieve proper ride height, which will ensure proper geometry and maximum stability. Progressive Suspension can be purchased at most motorcycle dealers or you can check out their web site by clicking on their button to the left.

Air Gauge by Progressive Suspension, Inc. has a redesigned screw-on connector with a new double o-ring connection, which completely seals the air valves insuring no-air-loss operation. This means that you lose no air when removing it. Their gauges are available in 0-15 psi, which is the one I am using for my 1995 GL1500SE, 0-30 psi, 0-60 psi, 0-100 psi and 0-200 psi. It is really easy to use and the only accurate way to get equal pressure on both sides. They can be purchased at your local motorcycle dealer or check out their web site by clicking on their button to the left.