FORK SHIMMING
First of all let me say that I was more than a little hesitant to try this myself, never having taken the forks apart before. It was no where near as hard as I had thought it would be. I believe that anyone that can adjust their own valves can easily do this.
The first thing you have to do is jack the bike and remove the front brake calipers from the forks. Hang them by bungee cords, not the brake hoses. This prevents you from damaging/stretching the brake hoses. Now pull off the front wheel. Set is aside, but don't rest it on it's rotors, so you don't accidentally bend them. Lean it against a wall out of the way. Now remove both axle pinch bolts and the left side axle "nut" that fits into the fork. Then unbolt and remove the fender.
At this point I decided to try to loosen the allen bolts in the bottom of the forks, hoping the fork springs would exert enough force on the damper rod to keep it from moving. This bolt goes up through the very bottom of the fork and screws into the damper rod. If the rod turns then you will have to make a special tool to hold it. On one fork I was able to completely remove the bolt. Be ready to catch the fork oil coming out in a suitable container. If the bolt doesn't loosen then you will need a tool to hold the damper. The top of the 95 model year (and on) damper is will accept a 15/16 inch bolt head. (I don't know what size fits the pre 95 bikes, it may be the same?) I found an appropriate bolt and pounded it's threaded shaft into a 15mm 3/8 inch drive socket. (Not a pretty sight, but it worked.) Next I loosened the upper triple clamps so the the tubes wouldn't distort when I took out the fork caps. After removing the fork caps and springs I just used a couple long extensions on the socket to reach the top of the damper rod and hold it from turning while I loosened the allen bolt on the bottom of the forks. Presto, out came the bolt and the fork oil. The hard part is over. Now I lifted up the dust caps on the forks and removed the retainer clips out of the top of the forks just above the fork seals.
Note: I still have not loosened the lower triple clamps and removed the forks from the bike. I did it this way because I didn't have a suitable vise to hold the forks in, so I figured I would let the bike act as my vice. It worked very well this way.
Now you are ready to separate the sliders from the outer fork tube. Simply grab the lower portion of the fork and lift it up and slide it down with a fair amount of force. It only took me one try. The bottom half slid off pulling out the fork seal and upper bushing. The slider is still on the bike. I repeated this with the other tube. Then I loosened all the clamps and twisted the sliders out of the clamps and pulled them free of the bike.
Next you need to inspect and clean everything up. I used denatured alcohol on everything. Try to keep the right and left fork parts separate so you don't mix them up.
On page 12-8 of the manual you can see all the parts. The cylinder base is a small piece that may stick inside the bottom half of the fork. If it does, turn it upside down and shake it out. Run rags soaked in alcohol through the lower portion of the fork and the inner portion of the slider. Get everything real clean. Now you are ready to reassemble and check for slop.
Push the slider back into the lower section of the fork, you don't need the damper or cylinder base for this. Then push the slider all the way down and slip the top bushing into place. You will most likely have to force the bushing down into the top of the fork. I used a couple large screwdrivers on each side and pushed it in using symmetrical force on both sides. One of them I had to gently tap in using a small hammer on the end of the screwdriver. After you have it fully seated you can slide the fork tube up and down and feel for slop. Check that it slides smooth and has no slop from side to side.
If you are like me you found some slop on at least one of the forks, if not both. Take it apart again. Ram the slider out (not too hard) and it will pull out the top bushing. Now look closely at the bottom bushing. You can remove it by getting a fingernail on the seam and opening it up enough to get it off the slider. Clean it up and then put a .0015 inch shim (feeler gauge) underneath it Stick it back in the tube and slide it. If you feel sticktion it is too tight. If you don't feel sticktion (the tube sticking and not sliding smooth) then go to the next higher shim, .002 inches. Continue the process until you find the shim that causes sticktion, then drop it back down one size lower. You can also trim the length of a shim to reduce it if you find yourself between two sizes. I put half of a .0015 shim in one fork and a whole >002 in the other.
Now you need to do the TOP bushing. This is the one that will get rid of the most slop, but it is also the harder one to do. Put the bushing to be "tweaked" on the slider, and slide it down so that it covers the hole near the bottom bushing (see page 12-8). Now strike (not too hard) the bushing right at the spot over the whole with a center punch and hammer to "dimple" it very slightly. Make sure the slider is resting on rags so it doesn't get scratched while doing this. Now reassemble and check for slop. The more you strike the bushing, the tighter it will fit, and the harder it will be to reinsert into the tube.
Expect to have to drive it in if you dimpled it very much. Kawasaki shows using a tool on 12-8 for this. I used screwdrivers and tapped it in as I mentioned before.
Check that it is not too tight. You want the slider to move with little or no resistance. Through trial and error you will get it right. Take it back apart, dimple it some more, reassemble, check for slop, repeat. Take you time here. Take a break and come back later if you want. Don't stop until you are satisfied that you have removed all the slop but it still slides smooth. Also, don't expect it to slide smooth at the two extremes of it's travel. The extremes don't matter, you want it smooth and slop free in it's mid travel points, and about three inches on either side. Don't be surprised if it feels just right in the middle, but feels tight at the extremes. This is because the extremes of the fork rarely get used and are not as broken in as the middle.
After you get the top bushing to the point that you are happy with it, take it apart one last time and insert the cylinder base. Reassemble and install the damper and torque the allen bolt (29 ft/lbs).
When you have both forks done, stand them up side by side and compare the sliding action of both simultaneously. They need to both have nearly the same level of resistance. Again, I am going to repeat myself, but they need to slide smoothly, with little or no resistance. SMOOTH, with NO side to side play. Don't give up until it's right.
Ok, your done. Reassemble with new fork seals carefully, don't use sharp objects like screwdrivers on your new seals. Some people drive them in with PVC pipe of the proper diameter to fit around the tubes. I have successfully used the old seals (cut in half) to drive in the new ones. Install the forks back on the bike and replace the springs (I recommend Progressive springs as a cheap [$45] way to upgrade your suspension) and fill with new fluid.
You are going to be surprised what a handling difference this makes!!! Both high and low speed handling is greatly improved. Well worth the effort (in my opinion).
Fred Harmon
COG # 2170
SCAD
Fort Worth, Texas
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