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Dyna Suspenson, Part II

Progressive Suspension meets Jeremiah's Hot Rod

By Bandit, and Sean from Progressive with photos by Wrench

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This is an easy one with a myriad of considerations. It’s easy because it’s a stock bike and Jeremiah changed his mind about being cool. He’s not lowering his scooter, and basically doesn’t want to mess with the stock configuration. There’s a world out there of guys who are beginning to feel that way. For us old outlaws who need to change and learn about everything, it’s a very scary thought.

Even lowering a stock bike doesn’t need to be a big deal. I spoke to Sean at Progressive and he told me the stock bike drill.

"As for your question about checking clearance," Sean pointed out, "it’s not needed if using our application fitment tool on the website and given the correct part # for a bike. In Jeremiah's case we used the application fitment tool on the website, looked up his bike and was given a part #. This part # is very bike specific. If we listed a part # for a certain bike it means we did a fitment check already and set the bottom out position in a safe location to avoid the stock OE setup from rubbing anything." 

So in stock bike situations Progressive takes the guess-work out of the equation.

Again, I’m going to run through some of the Progressive material with thoughts from the Bikernet Tech staff. All of our comments are edited and scrutinized by the Supreme Bikernet Performance Editor, Ray C. Wheeler, between dyno runs with his Salt Flats racer.

Stock H-D shock.
Stock H-D shock.


Lowering your motorcycle will decrease initial ground clearance. The motorcycle will be lower to the ground and care should be taken to avoid bottoming, especially over bumps or in turns. Lowering a motorcycle can change the
handling characteristics. Always use extreme caution when riding after a change is made and take time to get accustomed to any handling change.

These shocks can be mounted with the adjuster at the top or bottom. However, Progressive recommends the shocks be mounted with the adjuster at the top for ease of spring adjustment

The motorcycle must be securely blocked up or jacked to prevent it from tipping over when the shocks are removed. Failure to do so can cause serious damage and ruin your entire week and paycheck.

Jeremiah removing the stock shocks.
Jeremiah removing the stock shocks.

The use of lowering blocks on Progressive Suspension shocks is not recommended. Use of a lowering kit may void the warranty or damage the shock/motorcycle. Progressive Suspension shocks are designed to work on the OEM (original equipment) frame and swingarm.

Use of these shocks on a frame or swingarm other than OEM may produce an unsatisfactory ride and void the warranty.

Shocks are like a miracle drug to the right motorcycle. For the wrong motorcycle, they can be a dangerous nightmare. There are a number of specific golden keys when it comes to shocks. There is travel, spring rate, and dampening. I like to talk to shock wizards constantly. If you’re a dirt bike rider you know the significance of those amazing shocks with tons of travel. We are working with shocks with very limited travel. Then, if we lower a bike, travel is reduced.

The variety of Progressive shock mounting spacers in each kit.
The variety of Progressive shock mounting spacers in each kit.

Take one pair of shocks and throw a few variables at them, like speed, or two-up riding, or traveling weight, even a different seat changing your position on the bike. Try altering the front end. Then there are road conditions to consider. I often wonder how the hell anyone designs shocks capable of a silky smooth ride over a 2-inch bump at 25 mph. So what happens at 40 mph over a 2.5-inch bump? It’s nuts and you begin to understand the need for computer-operated ride control in cars.

Progressive Suspension is just that. They have been progressive to work with, constantly testing and trying different configurations on custom bikes in search of handling and ride Nirvana.

Make sure that proper bushings/sleeves are installed in the shocks. Improper bushings/sleeves can cause unsatisfactory and unsafe operation (see the instructions packaged with the mounting hardware).

1. Place a quality jack or sufficient blocks under the
motorcycle to securely lift the rear wheel slightly off the ground. Actually, you need to lift the rear of the bike until the wheel is resting comfortably on the ground, but with no stress on the shock. You will know immediately as you loosen the bottom shock bolt. If it glides you’re golden. If it doesn’t, you need to adjust your jack up or down.

2. Using the correct shop manual for your bike, remove the old shocks and note location of mounting hardware. If additional accessories are installed on your motorcycle, please refer to their mounting instructions for removal to gain access to your shocks.

Progressive Travel Limiters. They make a wide variety.
Progressive Travel Limiters. They make a wide variety.

3. Before installing your new Progressive shocks, you need to check the tire to fender clearance, making sure that the tire does not come in contact with the fender. If the rear fender or tire has been changed to anything other than stock, a travel limiter may be required. On some models with side bags or luggage, the bag or luggage mounts may
need to be modified to eliminate any interference.

JIMS tool for removing shock springs effortlessly.
JIMS tool for removing shock springs effortlessly.

Since Jeremiah’s bike was stock, we didn’t have the above issues, but with my custom FXR, we needed to remove the springs with a nifty JIMS tool, install the shocks and lower the bike until the fender touched or the shock bottomed out. In one case, we used several travel limiters, which made us very aware of how much our shock travel was limited. We had maybe ¾-inch of travel.

Checking the fender/tire clearance on the Mudflab Girl FXR. We removed the springs from the shocks and bottomed the shock against the bumper.
Checking the fender/tire clearance on the Mudflab Girl FXR. We removed the springs from the shocks and bottomed the shock against the bumper.

Install the shock assemblies onto the motorcycle with the included hardware, noting any special instructions in the hardware kit. Tighten bolts / nuts to their proper torque. Check the clearances of the shock to the frame, shock to chain or belt, shock to chain or belt guard and shock to brake caliper and linkage.

We did the above and determined which spacers to run. They were a tight fit in the shock grommets, so we used a ½-inch bolt and nut to pull them into place. Done deal.

4. Reinstall any accessories removed in accord with their mounting instructions. Make sure accessories do not interfere with the shocks throughout their full travel. If any accessories bolt to the shock mounting points, a careful inspection must be make to ensure that they do not bind the shocks in any way. The shock eyes should have a
minimum clearance of .02-inch to insure the eyes are not binding.

5. Set your ride sag. The proper spring pre-load setting will permit the rear suspension to sag, or compress, approximately one inch from full extension. To check sag, take a measurement from the center of the rear axle, straight up to a vertical point on the rear fender or frame with the shocks fully extended.

Then take a second measurement using the same points with the rider(s) on the bike. The difference between the two measurements is the ride sag. If the bike is sagging too much, increase the pre-load. These shocks are set at the factory to minimum pre-load.

6. Spring pre-load adjustments are made by turning the upper (long) cover. Turn this adjuster clockwise to increase spring pre-load and counterclockwise to decrease spring pre-load.

Above the adjuster, there are four grooves, these are pre-load reference marks:

Minimum pre-load = No visible grooves

Maximum pre-load= four visible grooves.

Set the pre-load equally on both shocks using these reference marks as your guide.

NOTE: The adjuster is a threaded device, so if you rotate the adjuster (upper cover) fully to the minimum or the maximum setting, you will
feel a sudden increase in rotational resistance as you reach the end of the range of adjustment. This sudden increase in resistance is the adjuster tightening against its stop. When you feel this, we recommend that you turn the adjuster back from the stop by approx ¼ turn.

This will facilitate easy adjustments in the future. If the adjuster is tightened firmly against the stop, either at minimum pre-load or maximum, you
may have difficulty re-adjusting the pre-load by hand. Should this occur, the use of a strap wrench or similar tool will give you the needed leverage to rotate the adjuster away from its stop and return it to normal operation.

7. Test ride: If excessive bottoming occurs you need to increase your spring pre-load setting as described above.

Progressive Suspension warrants to the original purchaser of this part to be free of manufacturing defects in materials and workmanship with a lifetime warranty. In the event warranty service is required, you must call Progressive Suspension immediately with a description of the problem.

If it is deemed necessary for Progressive Suspension to make an evaluation to determine whether the part is defective, a return authorization number will be given by Progressive Suspension. The parts must be packaged properly so as to
not cause further damage and returned prepaid to
Progressive Suspension with a copy of the original invoice and a detailed letter outlining the nature of the problem.

If after the evaluation of your report by Progressive Suspension board of directors, and no spelling errors are discovered, and the part was found to be defective, it will be repaired or replaced at no cost to you. If we replace it, we may replace it
with a reconditioned one of the same design. Your parts will be fixed at the exclusive Progressive Suspension Reconditioning facility in Rattlesnake Gulch in the Mojave Desert, and you are required to retrieve you components on foot with the original invoice in hand.

Click for more info.
Click for more info.

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