To bring the discussion back to the origianl shock in the thread,
here and
here
Here is the pictures from the shock tear down: (Note the shock is in the vice upside down) It is dirty from the last ride which included about 20 miles of gravel road going down the Burr Trail in September. See the gravel laying inside the spring.
Notice the thread damage covering 3-4 threads (from top of picture). Thanks to Fairlainer's reference and pictures in the
Missing mud flap thread on a 2013 and Ahchiu's link to where you can buy the inner hugger rear fender, I now have a rear hugger going on my bike to further protect from gravel and other debris being thrown at the shock.
Also you will notice the black plastic that protects the braided line from damage has some wear about halfway down it. This is from rubbing on the swing arm. I have rerouted the line to prevent it from rubbing on the swing arm.
The oil and solids in the oil from it breaking down over time (some of that is air but mostly solids suspended in the oil). What is missing is the smell that goes with the breakdown. Picture the smell of a septic tank on steroids. Stinks really bad.
Notice all the dirt that came off outside the shock laying on top of the vice.
Internals, not all the solids in the oil again
With the plunger removed, you can see the dirt and grime
plunger removed
top of resevoir
Inside of resevoir, note again all the solids in the oil
another shot
shims stack - you can see all the wear the solids did to the shims. They are stainless steel - I don't know what grade
Moral of the story, don't let your shock go too long before maintenance. Because I went too long, in this case 27,870 miles, I had to rebuild the shims stacks which cost about another $150 to the maintenance. With the riding I do, I probably should be getting it done about every 15,000-20,000 miles at the worst case or every two years.
If you find you have window of a couple of weeks where you can pull the shock and send it in. It might be worth it to you. For me that convenient window is during the winter. I'll be doing mine in the winter if it is close to being due on mileage or I can't make it another season, I'll pull it early and send it in.
I do run my shock pretty hard because I and riding two up, towing a trailer and playing in the twisties most of the time. To me it is worth the cost to keep it perfoming like it should.