Performance gains
Here are the main performance gains I have noticed with the Works Shock.
First of all, the spring is stiffer, and this makes the whole rear end feel more solid. It does not squat as much in turns. The increased spring rate results in less sag, so the rear end does not sit as low. The end result is more ground clearance so I don’t drag pegs as easily. High speed riding is also vastly improved with the new spring rate, as the bike is more firm and does not tend to wobble or pogo on high speed sweepers like it used to.
The increased rebound dampening also greatly helps. After an impact, the rear end settles much faster than before. This accentuates the overall tighter feeling that the new spring provides. It is most noticeable when you are leaned over in a turn that has some rough spots or dips in it. In my opinion, this is one of the true tests of a good shock setup. Find a corner that has some undulations in it and see how the bike handles when leaned over (nearly to the pegs) and you hit the bumps. If the bike stays taught and does not loose it’s line, then the shock is properly dialed in. If the bike begins to pogo (bouncing front to rear) and looses it’s track, then the shock is being overcome and cannot contain the forces put on it. This is another place where the Works shock shines. When pushed to extremes like this, you really begin to appreciate the tighter spring and rebound dampening. The shock maintains the bikes composure at all lean angles and speeds that I have been able to ride at. I have several test corners that have some good bumps in them, and with the new shock, the rear wheel maintains grip and contact and the front end does not pogo or loose track.
I am able to add about 10mph to my entrance speed on all corners as a result of the Works shock. While you may not ride hard enough that this matters to you, consider the safety aspect of increasing the handling envelope that the bike can tolerate. In an emergency, that extra 10mph could make a difference. For instance, when you enter a corner too fast or overcook it (which we all occasionally do). How the bike (and you) handles the increased speed and lean angle will make the difference between an accident and just a puckered seat.
Some folks have changed out the spring to the Progressive unit, and while this helps, it only addresses half of the equation. If you add more spring force, you also have to add more dampening force to counteract it. The increased dampening on the Works shock is adjusted to work in concert with the new 1,100 lb spring rate. And it also is adjustable via an Allen head adjuster on the bottom of the shock. This allows you to dial it in, within limits, to your liking.
If you are getting a new stock shock from the dealer for free, then I say by all means take it. The stock shock does not do a bad job unless loaded (two-up), but it looses its performance pretty fast. At 30K miles I removed my original shock and replaced it with a new OEM shock that I got a hold of. I was amazed at the improvement. My OEM shock had gradually been going downhill for a while, but I didn’t notice it because the change was so slow. Once I put a new OEM shock on the bike it was obvious to me how much my original shock had degraded in performance. And the real kicker is that you can’t buy the OEM shock or spring by itself. You have to buy the shock, spring, and preload adjuster all as one unit for about $1,000. This is another thing makes having a rebuild able shock attractive.
Under two-up and fully loaded riding conditions, the Works shock also shows a marked improvement. The increased spring rate means the rear does not sag as much and the increased dampening means the bike doesn’t bounce after impact. As a result you have more ground clearance. You also don’t have to add as much pre-load to the adjuster unit. When I ride one-up I can typically leave the adjuster at zero or maybe 5 but no higher. When two up and loaded, I run it at about 12. With the OEM shock, I had to run the adjuster at 21 single, and 25 with passenger and luggage, and it still wasn’t enough for my tastes.