I will start this by saying if I knew it was only $100 to have a professional at Race Tech or Procycle rebuild a shock, I would've seriously entertained that. I'm glad I didn't. I learned a lot about hydraulics and patience.
To start with, I purchased a Shock Solution Kit
from Procycle after discussing my (lack of) riding style and the fact my height was too short for my weight. After the last ride where I pushed the DR hard and bottomed out the rear (hearing "kachunk" yelled on the radio from a rider behind me) about 10 times....it was time for some upgrades. The DR is well known for being softly sprung, pretty much set up for a 170 pounder with a mild riding style.
The Race Tech
instructions along with the Procycle Installation Guide
helped as I muddled along. Both Procycle and Race Tech support lines were very willing to help and had top knotch customer service.
After watching the hour long video included with the Gold Valve, I got started.
Stock shock removed
Leaving an empty center section after taking out the airbox, carb intake, etc.
Took a variety of photos to document the order of the parts as they were removed.
After bleeding off the 175 PSI of nitrogen from the bladder, I made a special tool called for by Race Tech. Didn't price theirs, but mine was in a bucket in my garage.
After removing the bladder and popping the cap off of the main shock tube, I used the tool to depress the seal head into the tube far enough to access the clip ring.
Note: I should have cut the PVC in half as to not have so much length pushing into the tube - made it hard to remove the tool to access the snap ring. I cut it - now I have two!
The nitro bladder, shaft with stock valve, seal head, etc & the body.
IMPORTANT: Race Tech warns (and for good reason) about taking the nut off of the shaft. It has internal and external peening (smashed onto the shaft) and will not come off without breaking something unless you follow specific steps to properly grind off the peening. With the DR it's not as critical because there isn't an adjustable rebound valve in the center of the shaft. Mess up this step and buy a new center shaft. I'd vote for if you have adjustable rebound damping on your shock, have a pro grind the nut because the internal peening holds the damper valve in the shaft.
Sooooooooooooooooo, my new center shaft arrived.... kidding. I did mess it up a little but was able to recover with a 12mm x 1.75 die. Race Tech provides you with a replacement nut for either a 1.25 or 1.50 pitch, but not the 1.75. Procycle said they've never heard of a 1.75 being on there but I took the nut to two hardware stores to check the pitch prior to buying a die and replacement nut.
Put the guts on a bolt in the order removed so I could keep everything straight.
Race Tech provides you with a one time access code to their valving computer online. Go to their site, enter bike, slow fat old guy (in my case) and it spits out the valve stacks for High/Low Speed Compression and Rebound damping. Also provides spring rate, compression adjustment and fork set up in case you buy their emulators.
Broke out the caliper and bought a digital micrometer and got to work on the valve shims. Race Tech provides you with some popular stacks pre-bagged. No such luck. Dump 'em out and start measuring.
Organized the shims by outside diameter and thickness and got the stacking order from the recommended settings.
Built my stacks for the Gold Valve and drilled the required 5/64" hole in the valve per instructions.
Intructions say to "surface" the base washer using 320 grit sandpaper and a piece of plate glass (since it's flat). Home depot has small panes pre-packaged for under $2.
After filling the bladder tube with SHOCK FLUID, I pushed the bladder in and installed the snap ring. Fluid is supposed to spill over to prevent air from getting in, hence the cat litter box. Zap it with 40 PSI to seat the bladder and fill the main tube. The newly built main shaft with shim stacks and Gold Valve are cycled to get air bubbles out. Special tool used again to push seal head down as you release the bladder pressure. Snap ring, zap the bladder with 20 PSI to seat the seal head and reassemble the remaining parts.
Brent (BC330) at MotoWorld got me right in for a recharge on the nitro and back in the bike it went. Lubed all the pivot points and cleaned everything I could access prior to install.
If your just changing the fluid, which IS a maintenance item, this is a pretty simple task. My shock fluid was milky and a bit foamy (probably from all of the water crossings) so it was good I took this on.
CAUTIONS: Race Tech tells you in the instructions to buy some RED loctite for the nut re-install. They also mention lubing the seal head and shaft as you install new pieces. Shock fluid in the kit is RED and provides a ready lube. Even though RT tells you to go buy some loctite, they actually provide a small vial (unmarked) with the kit...see where this is going? DO NOT use their little red vial of possible shock fluid to lube anything.
As I slid the seal head (lubed - I thought) onto the shaft, followed by the base washer and shims, valve, etc......my fingers were getting sticky.
3, 2, 1....S$%#.......ripped everything apart and soaked in Kerosene, brushed, rinsed, dried, (properly) lubed and re-assembled.
A great learning experience with some tech support help and BC330 comin' thru in the end.