

⚡ Elevate your ride with shock performance that means business
The Progressive Suspension 412-4003B is a 13.5-inch heavy duty rear shock designed specifically for motorcycles. Featuring a steel double wall damper with multistage velocity sensitive damping, a 5-position cam style preload adjuster, and high-pressure gas charging, it delivers consistent, customizable suspension performance. Finished in black with a durable progressive rate spring, this proven 412 Series shock enhances ride quality and durability for serious riders.
| Brand | Progressive Suspension |
| Auto Part Position | Rear |
| Style | Heavy Duty |
| Vehicle Service Type | Motorcycle |
| Exterior Finish | Chrome,Steel |
| Material | Steel |
| Extended Length | 13.5 Inches |
| Automotive Fit Type | Vehicle Specific Fit |
| UPC | 953040129289 |
| Manufacturer | Progressive Suspension |
| Model | 412 Series 13.5in. Shocks - Black |
| Item Weight | 9.68 pounds |
| Product Dimensions | 17 x 6.75 x 3.5 inches |
| Item model number | 412-4003B |
| Is Discontinued By Manufacturer | No |
| Manufacturer Part Number | 412-4003B |
C**E
Easy to mount. Work great. No adjustment instructions, so here's HOW TO...
To be truthful, these are the ones I sent BACK. I needed the chrome 12.0 inch for my 2009 VTX1300C, which they sent right away at no cost or hassle to me and gave me a label to send back these via FedEx, no problems. Now for what I DID get... Look good. Very easy to put on the VTX withOUT using the lift, which surprised me. Took about 10 min to do each side. Then came the time consuming part. Adjusting them. The instruction DO NOT come with load suggestions. IMPORTANT: You have to do the 3/4 inch sag test. You take a measuring tape ruler/measuring tape and, with the bike upright, but no weight (including in your bags) measure from ground to middle of rear tire axle. Then sit down and measure it again (it takes two people to do this). You make adjustments to the shocks until you get a 3/4 inch only compression (sag) of the shocks for the weight that will be on the bike. It would have been nice if they'd bothered to put that in plain English on the instructions so you didn't have to call them to find out how to do it. They will NOT tell you where to set the shocks, just how to set them. The choice is ultimately yours. The shocks are set for minimum out of the box. I carry a lot of gear and my wife sometimes hops on to ride 2UP unexpectedly, so I moved it up to one notch below max. Rides pretty stiff solo, but works great with both of us on and heavy baggage.
I**N
The best upgrade ever!
I have a 2010 Harley-Davidson sportster 883 and the bumps were killing me. My bike would bottom out all the time so I got these Progressive shocks. They are amazing, my bike rides so good now. These shocks lifed my bike like 3 inches and I had to adjust the back tire as the belt was too tight. Im 220lb and 5.5 tall. I'm going to do the front next and I will upgrade my kickstand as it will be too short. It's crazy how bad the OEM shocks are.
D**L
Great for my needs
Install was pretty straight forward. Undo the old set and put these on in their place. I didn’t have a bike jack so I used the scissor jack from my car and a stack of 2x6’s to lift the bike and support it like a center stand as I worked. The stock springs on my 2018 Iron 1200 were 11” so I had to lift the bike up quit a bit to make room for these 13.5’s. After making such a change in shock length I had to adjust the rear axle back a bit to take up the slack this created in my belt.I love the look of the stance these shocks gave the bike. I think the slammed look is okay for some set ups and can be a fun ride, but it’s not my preference. I weigh 150lbs and find the standard shocks to be on the stiff side. The stock set was stiff too, but it had to be because there was almost no travel on the 11’s. I thought going to 13.5“ would give me a little smoother ride with the added suspension travel, but I guess I’m not heavy enough to compress the shocks that much. The ride is good even though these feel a little stiff. The biggest difference for me is cornering clearance and the taller stance of the bike. For the price I’d say these are totally worth it if you want to change the aesthetic of your bike like I did. If your looking for performance out of these (other than clearance like in my case) I’d probably look at a more expensive set up unless you’re on some 10” slammers.
B**.
Great!
2018 HD Sportster Forty-Eight: First bike and wasn't a bad install. The directions could be better. It is night and day difference compared to the stock shocks. Definitely more comfortable and has way better handling. I went with the heavy duty version being 6'3" and 240 lbs. Took it for a ride and couldn't any more happy.
N**X
Good shock
Stuff ride if you’re under 180 but better than OEM even on big bumps
M**I
CX500 C install
These shocks are great on the '80 CX500 Custom I'm working on. Waaayyy better than the stock ones, and not too expensive for good shocks. Cheaper ones can be had, but they're just that-cheap, and why use $1000 shocks on a $1500 bike? Anyways, these are about an inch taller than stock, but allow more/proper sag. They also level out the bike, so rake/trail change slightly. No big deal on a bike like this, but if you're concerned. ... You'll also have to drill out the included spacers to fit on the shock posts.
D**C
Excellent Product!
These fit perfectly. I replaced the rear air shocks with these and I am glad I did. No more messing around with getting the correct air pressure. The ride is great. I would definitely recommend these to my friends. By the way, I put these on my 1988 Kawasaki Voyager XII. The bike rides perfectly level now and I can tell the difference.
B**B
Game changer
These are great! Made my 30 minute commute smooth and my butt happy.
Trustpilot
1 week ago
1 month ago