Progressive Suspension 444 Series


A lot of riders go straight for the power upgrades when they begin to modify their bikes. That’s understandable, we all want that perfect rumble and throw-you-back throttle response, but don’t forget how your bike rides. Stock shocks have gotten better over the years, yet they still are not comparable to the best aftermarket shocks like those from Progressive Suspension. If you really want to improve your Harley, you need to check out the Progressive Suspension 444 Series shocks to feel how your bike is supposed to ride.

At Progressive Suspension, they make shocks for everyone with options in different categories they refer to as Good, Better and Best. The 444 Series shocks are in The Best category and have all the tech and specs to back them up. When you put these shocks on your Harley, you can be confident that you will have a sweet riding machine.

The biggest feature that makes the 444’s so great is the Frequency Sensing Technology (FST), which is a type of valving that allows the shock to dynamically adjust damping as you go down the road. This process’s function is to help separate the movement of the wheel from the chassis or in other words, to prevent the movement of the wheel from moving the chassis (and you).

The FST technology creates a “sweet spot” in the shock by using deflective disc valving. During the compression and rebound of the shock, the valve will actually leak inside the shock so that it can still dampen while going over the small road imperfections like tar strips and small cracks. When you hit a larger bump, the valve system will close and force the oil to move from one side of the piston to the other to provide ultimate shock absorption. The shock will then rebound just as quickly as it compresses to keep the most possible tire contact on the ground.

Another key feature on the inside of the 444 shocks is that Progressive Suspension fills them with nitrogen instead of air and the nitrogen is completely separate from the oil. Air filled shocks can be affected by temperature as air will increase in pressure as it warms. Nitrogen will not and is ideal for having consistent performance in all conditions. The separation of the gas and oil is important because if the two can mix, the oil may become foamy and will not perform as well as it should.

The 444 Series shocks also feature the latest in construction methods. They are now an all-aluminum construction, aside from the spring and rod. The eyelet is no longer welded on as well. What you get is a set of shocks that are four pounds less than previous models and are a sleek design that is available in either black or chrome.

Installation of these shocks is fairly easy to do. They are a traditional shock so you won’t need to make any modifications to the motorcycle in order to install them. There are Heavy Duty Applications available to use for bikes that are operated at or near the manufacturer’s maximum load rating over 50% of the time.

Progressive Install

Once you install the new shocks, it’s important to set the ride sag of the motorcycle’s suspension before going for a ride. Make sure that you set the sag according to the load that will be on the motorcycle when you are riding. If you sometimes ride with a passenger or with more luggage, you should adjust the pre-load of the shocks. Fortunately, adjusting the pre-load on the 444 Series shocks could not be easier. They feature an adjustable collar that can be turned easily by hand, eliminating the need for a spanner wrench.

So go ahead and make all those performance upgrades, but don’t forget about your suspension along the way. The Progressive Suspension 444 Series shocks will make your Harley feel like you are floating on clouds as you go down the road.

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14 Responses to “Progressive Suspension 444 Series”
  1. dave

    I just bought a 2013 leftover Ultra limited anniversary edition, I hate those damm air shocks, Im interested in something like this im 300 lbs pass is 115-130 depending will this shock work for me?

  2. Sid Newsom
    Sid Newsom

    I have a 2015 Freewheeler FLRT Trike. There is a 444 model for trikes, but the problem is not being able to adjust easily and the forums say to install upside down. What do you think of this? I’m an old biker with a bad back which is why I’m riding a trike. Other option is something like a Legend Aero-A for trikes. Any experience as to which will be more comfortable for my missing disc? I need to buy one or the other. Thanks.

      • Sid Newsom
        Sid Newsom

        Thanks for the feedback. I agree that they are both good choices with pluses and negatives. For a trike, my FLRT in particular, the 444s seem a better choice because they don’t have the possibility of loosing air and dragging the pipes, which is my biggest concern. The trikes sit too low. The Tri Glides have a lifting kit that people use, but no such deal for the Freewheeler. I drag easily coming out of a driveway for example. I had 944 progressives on my ’09 Road King but it lowered it enough that I was scraping pipes if not careful. I am thinking I should stay with the stock HD air as they can run empty and not lower the trike (which I found out recently after my first service as the dealership left the shocks empty). Am I worrying about that for nothing? Thanks.

        • Customer Service Techs
          Customer Service Techs

          It’s a valid thing to scrutinize over as it can be a safety issue. There is nothing wrong sticking with stock HD shocks.(ZD: 2487)

      • Sid

        Hi guys. Just a little feedback after all the research. Thanks for your input. Talked to Progressive and the 444 shock for Freewheeler was designed just for the trike. It has issues with being a bit too low, so they made it 13.5 inches to put it a bit higher. That’s perfect as I hit bottom coming out of my driveway if I’m not careful. And he said that even if I put the preload to minimum it will not sag, which is also perfect, as that is pretty much where I need it for a soft enough ride for my back. All the air suspensions are max at 13 inches as far as I can tell, and if they loose air they drop all the way down. Just too much of a hassle, so I ordered the 444s. I am an engineer and way over think this stuff, but I am convinced this is the right way to go. Thanks again.

  3. John

    I have a 2012 Tri-Glide Ultra. Was running well until the 2015 season The rear end has become unstable. Played with different air pressures on the shocks no good. Two dealers checked out the suspension no problem found. I jacked up the trike and let all the air out of the shocks using the Harley pump. I pulled the air hose off the right shock and then the left and I had a puff of air come out of the left shock. Do you think I have a bad left shock? Its hard to handle on straight away and worse on curves. Thanks

  4. Rose

    Where do I go for advice. I ride a 2013 triglide. Every once in awhile the bike will not start. Emergency flashers come on but no computer delay on the dash. i have been to two dealers with no hint of what the problem might be. Of course the bike starts fine at the dealers. Any thoughts on this problem?

  5. jeff

    i ride a 87 Electra Glide Classic. got a heck of a deal on ebay on a set of Progressive IAS412 12″ shocks to fit my old geezer glide. best 200 bucks i think i`ve ever spent…

  6. Michael

    Hi I bought a set of 444 13//.5 HDrear progressive shocks for my triumph rocket 3 I’m happy with the shocks the ride height is a Little bit higher . Is this ok it seems to be good .just woundering if the shocks are strong enough for my bike?