I decided to celebrate presidents day by changing the fork seals on the dirt bike. It was actually a lot easier than I had imagined - although it does take a while. Don't be intimidated by all the crazy parts you see in pictures of open forks. Just make sure you take apart 1 fork at a time, and that you keep the parts in order. Also - you don't need a hex wrench... that's to remove the compression adjuster - which you do not need to do when replacing fork seals.
Here's the break-down of the procedure...
(note: if any of these items aren't familiar to you - you'll figure it out while working on the forks... it's not as bad as it sounds)
1) get a flat head screw driver and soften the rebound and compression (back the screws out). Warning - once you meet resistence - stop backing out the screw, do not force the screw out more than it will easily go, or you will cause damage.
2) loosen (do not remove) the fork cap.
3) remove the forks
4) remove the fork cap
5) pull down the fork spring, insert a 17mm wrench, and remove the fork cap from the fork piston rod
6) remove the spring, and measure to ensure it does not need to be replaced (the spec is in your service manual)
7) dump out the fork oil by fliping fork over.
pump fork piston rod up and down
9) repeat steps 7 and 8 several times until no more fork oil comes out, and fork piston rod moves freely up and down
10) get a knife, and carefuly pry out fork cap
11) get a flat head screw driver and carefuly remove the circlip
12) this part may seem weird - but this is what they recommend in the service manual... grab the top of the fork with one hand, and the bottom with the other, then yank apart. This will take several hard yanks - because you are "hammering" out the oil seal. Be careful not to drop the fork tubes when you finally get them apart.
13) once apart, remove the top bracket by separating it, and sliding it off the top. (don't separate it any more than you need to)
14) set the top piece on a table, and remove the remaining pieces by sliding them up the fork tube. Make sure you keep the piececs in the same order you removed them
15) put grease on the fork seals
16) put plastic over the end of the fork tube (I used a sandwich bag) and lube the remaining pieces with fork oil.
17) slide the pieces over the plastic, onto the fork.
18) after the oil seal is on, remove the plastic, and put the remaining pieces back on.
19) cut the old oil seal in half, and use it to hammer in the new oil seal. This part takes a long time, since you don't want to hammer too hard - and you still have loose pieces. Some people like to hang the fork from the ceiling so they can hammer down - but I simply put the fork on the floor, and up against the garage wall, and hammered to the side.
Then put the circlip back on, and the oil seal.
20) pour the specified amount of oil into the fork tube (or as much fits)
21) pump the fork piston rod several times
22) pour the remaining fork oil into the tube. (for my bike - about 570ml per fork - note that for both forks, this requires TWO(2) bottles of fork oil).
23) let the fork settle for 10 minutes to ensure as much air is out of the system as possible.
24) measure the distance from the top of the tube, to the top of the oil, and ensure this is to spec, if not, add/remove as needed.
That's it in a nut shell.
It's not as complicated as it sounds - but it will take a long time. There's really only 1 way it all comes apart and goes back together, so once you start the project - it all makes sense.
