My 2 cents on these shocks on my 2006 VTX 1800C. I'm sure these work for a lot of folks so don't get your feathers ruffeled. I just want to post how they worked (or not) for me so others considering them can make a more informed purchase.
3-22-06 I tried the Progressive 440 Standard model rear shocks with standard springs for the 12.0” length. This is 1/4" shorter that OEM and slows the steering a little a reduced ground clearance some. The 12.0” shock comes with the 210/250 lbs. as standard and is the lightest spring they furnish for this length. (In comparison, the 440 Heavy Duty model has a 270/315 lbs. spring.) The shocks have good dampening at the low spring pre-load settings but the 210/250 lbs. spring was too stiff overall for solo riding at any spring pre-load setting for my 180 lbs. body weight. Not enough sag and too harsh of a ride even on the lowest spring pre-load setting. They were great riding two up with baggage (approx. 370 lbs. total payload weight) on the lowest or the second spring pre-load setting. Any higher spring pre-load was too stiff to provide a smooth ride and the valving did not offer enough rebound dampening at the higher spring pre-load settings to slow the shocks extension. This produced a “pogo stick” action from the shock. This proves the 210/250 lbs. is too stiff for my weight or anyone solo riding weighing 220 lbs. or less in my opinion and the baseline valving is too light. Through conversations with Progressive, they admit they use heaver springs than what would be ideal for a given rider weight. This is done to protect the shock from damage as a result of bottoming the unit and to avoid warranty issues as a result of bottoming damage. In my opinion they take this too the extreme.
12-10-09 Purchased Progressive 440 Standard model 440-4209C rear shocks with standard spring for this
length of 12.5”. The springs have a 120/170 lbs. rating which is standard for this length.
$ 471.71 from ALL BIKE SUPERSHOP. This shock works great for solo riding. Much better than
the worn out OEM units. The additional shock length of ¼” helps the “turn in” of the bike. It easier to make quick steering changes. Initial sag is obtained and swingarm movement is very controlled using one or two turns of spring pre-load. Unfortunately any more than two turns on pre-load causes the shock to rebound to aggressively and does not allow for enough initial suspension sag for solo riding. The shock dampening does work well at the lightest setting but only in a narrow spring pre-load range. The AIS dampening feature does very little (if any) to compensate for added spring rate change. As the preload is increased, so does the rebound speed. Due to the lack of change by the AIS valving, the shock becomes a “pogo stick”. Riding two up was not what I hoped for either. Even on the max spring preload setting of five turns, our combined weight of 310 lbs. was too much for the shocks. Bare in mind we had no baggage on the bike during the ride and this is below the GVW rating of the bike. The shocks bottomed out four times during or 200 mile test ride over bumps they shouldn’t have in my opinion. They bottomed on bumps during slow and high speed compression cycles traveling moderately bumpy roads. These are roads conditions the OEM unit springs could have handled easily. A very rough road would have certainly bottomed the 440 shocks harder and more often. This supports my opinion the AIS valving does little to compensate for suspension speed changes whether it be from increased pre-load or road induced.
My general impression is that the Progressive 440 works great in a narrow range of weight for a
given spring rating based on their suggested spring weights for rider weight. However they do not
provide enough rebound dampening over the entire spring pre-load adjustment range for ANY
spring rating they offer for either of the two lengths I’ve tried (12.0” or the 12.5”). They will
however, dampen well in only a narrow spring range at or near the lightest spring settings. Unfortunately when the spring pre-load is increased to ride two up or with baggage, the baseline dampening built into the shock is not enough to control the added spring rate.
I feel the AIS valving does very little, if anything, to increase compression or rebound dampening when the piston speed increases. Can you say “Marketing Ploy?” I agree with the concept of a “variable damping rate valving reacting to piston speed” (that’s what the AIS is suppose to do) and that it is beneficial and desirable in a shock, but Progressive’s AIS system does not produce this in my opinion as determined from my years of experience racing and tuning motorcycle suspensions and my butt dyno using the two 440’s I’ve tried. Progressive also misses the mark when it comes to recommending spring rates for rider weight in my opinion. This shock would work much better for me if they offered a 170/210 lbs. spring, unfortunately they do not. They only offer three spring weights and I beleive the middle rate is too heavy for the average 175 lbs. rider. The OEM spring was pretty close for my weight both for solo and two up riding. Give Honda the credit there. Progressive suggests the 210/250 lbs. spring for my 180 lbs. weight, but this is 20-30 lbs. per inch too stiff for solo riding even on the lowest setting. The 210/250 lbs. spring is more suited to a 225-240 lbs. person riding solo and two up riding. Unfortunately the dampening will not be what it should be when the pre-load is raised to compensate for the extra passenger.