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Fork Oil Replacement.

Notes:
Top Yoke nut is 30 mm
Fork Caps are 22mm
Each fork takes about 19 oz of oil.


Tips:
*Measure fork oil with a graduated wooden dowel, marked at 160mm, 166mm and 170mm.
*Lube each bottom shroud’s wiper before re-assembly.
*Break loose each fork cap after job completion to burp the air out.
*Removing the tank is optional.
*Compressing the fork after spring removal is easy. This is the fork’s natural state.
*Sometimes the fork’s inner tube will seem to stick when all the way inside the outer tube. Tap gently at the junction or rotate and pull up on the inner tube.

Procedure
Front Wheel Removal
*Break free front axle using 12mm hex on right side of axle. Unscrew it till about 5mm of thread is still engaged. Leaving the pinch bolts tight.
*Remove clip holding brake line
*Free up the speedo cable where it passes though fender’s loop or liberate the rubber loop from the fender.
*Remove front rotor’s caliper. Support it. Break free retaining pin before removal if ya want to clean up the caliper or change pads.
*loosen front axle’s pinch bolts.
*Jack bike up.
*Gently push on the axel’s right side bolt you left 5mm screwed in, partially driving the axel out to the left.
*Remove Axel’s bolt
*Remove axle to the left, catching the right spacer should it fall out.
Jack bike a bit higher,
*Remove wheel paying attention to the speedo drive and the right spacer
*Place speedo drive in plastic bag, support it if needed.
Fender removal
*Remove fender bracket to fork bolts, paying attention to the brake line bracket’s clip position on the left forks’ rear bolt.
*Remove fender
Fork Removal
*Loosen each fork’s cap.
*Tape off each forks fender attachment points.
*Remove the two bolts holding each fork’s lower shroud.
*Slide each lower shroud down to the tape cushions you just made.
For one fork,
*Slacken the lower yoke pinch bolt.
*Slacken the Upper yoke pinch bolt.
*Remove fork by pulling down until it clears the upper shroud and bottom yoke.
Now the other fork
*Slacken the lower yoke pinch bolt.
*Slacken the Upper yoke pinch bolt.
*Remove fork by pulling down until it clears the upper shroud and bottom yoke
*Remove lower shroud by lifting up the fork until it clears the top of the inner fork tube
Fork Oil Removal
*Remove cap using 22mm soket applieng pressure to prevent the cap from launching upward on you.
*Remove spacer (stock spacer is 190mm in length)
*Wipe thread of fork tube paying attention to remove cleany the bits of metal from the threads.
*Remove washer.
*Remove spring.
*Invert fork over collection container
*Pump fork several times
*After several minutes, hang fork upside down, placing old towels or paper towels under fork to catch the drippings.
**Repeat for other fork.
****Clean Up prep for fork oil fill.
****You should allow the forks to hang upside down for a while. Break out the ****simichrome and polish up the forks inner tubes. Outer tubees and the lower yoke ****and upper yokes. The shrouds, the bolts. Clean up the caliper too, replace the pads ****if you need to. Clean up the fork spacers and examine the springs and the washers.
*Before righting each fork after draining, take a lint free cloth and wipe the inner tube’s cap threads off again.
One fork at a time…
*Right fork. Lean it in the open corner of one of your workbench drawers.
*Pour in 19 oz of fork fluid.
*Pump fork several times.
*Repeat for other fork
*Measure Fluid Height
Hold fork vertical, dip your marked, wooden dowel into the inner tube to the 170mm mark. Withdraw and look for fluid. Add fluid until you see about 4mm of the dip stick’s bottom wet. Or to whatever height you want the fluid to be below the inner tube’s upper lip. I allowed for the dowel to be wet for a height of 2mm, yielding a fluid height at 168mm below the inner tube when the fork is fully compressed. Progressive springs, more displacement so a slightly lower fluid level in the inner tube.
*Replace fork spring
*Replace metal washer
*Replace spacer
*smear some fork oil on the fork caps’ o-ring.
*While exerting downward pressure, and holding the inner tube up, replace the fork cap and tighten to hand tight paying attention to not cross thread the little bugger.
*Place lower fork shroud on each fork.
*Slide each fork into lower yoke then through the shroud into the upper yoke.
*When fork inner tube is flush with the upper surface of upper yoke, tighten lower yoke pinch bolt.

Repeat for other fork.
*Re install each fork

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The job is pretty easy and straight forward. Just have someone hold the bars out of the way and it goes easier. Takes all of 15 minutes if your oil is nice and clear still.
Remove the two large caps on the tops of the forks, they are spring loaded so beware and hold on. Once you get the cap off, take a metal coathanger and bend a little hook in the end of it. Reach down inside the fork and hook the old spring and lift it out slowly, as not to spill the oil all over like I did. Check the color of the oil, if it's clear it's good still. Notice the positioning of the springs and spacers for reinstall. Put the new spring in with the compressed/tighter wrap spring part down in the bottom of the forks. Reassemble, tighten cap nuts and ride.
If you are going to change the oil, suck it all out with some vinyl tubing stuck on the end of a turkey baster. Cheap and easy to do. Then pour in the desired amount of oil, and check the oil height with a dowel rod stuck down the forks as a measuring guage. Get them both the same hieght (whatever the measurement is, mentioned above) and you're good to go.
By the way, there has been a lot of talk in the NTBF about this and they seem to think that a 50/50 mix of 10 and 15 weight is the ticket with the front progressive springs.
Good luck.

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It's not as bad as the manual makes it out to be. Really all you need is a good measuring cup, and a wooden dowel to stick down inside the fork to measure the distance from the top of the fork tube to the fork oil once you've poured it in(insert dowel till it dips into the oil. Hold it steady and mark the dowel at the top of the fork tube with a Sharpie. Take out dowel and use a tape measure to measure the distance from the mark on the dowel to where it where it starts to get wet with oil).

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Unscrew the fork caps(being careful by putting your hand over the nut, because they can spring out like a Jack-in-the-box), Take out the old springs using a coat hanger with a little hook bent on the end, and put in the new ones. There's also a spring seat and a spacer on top of the the springs, so watch out for those and remeber which order they go back in)If you aren't close to a required fork oil change(24,000 miles or 4 years), I wouldn't sweat it.

If you want to try the 15w fork oil, then it's more involved. Best to get a shop manual if you don't have one, and you don't feel all that sure of what you're doing. If you're confident, then you'll want to take the forks off, drain the oil into a pan. Measure out 548cc(18.5 oz) of fork oil and pour it in. Then pump the fork a few times to get any trapped air out of the oil. Fully compress the fork, and then let it sit a few minute to stabilize. Use a wooden dowel(found at any good hardware store), and stick it down inside the fork till it dips into the oil. Holding the dowel firmly against the edge of the fork tube, take a Sharpie and mark it at the top of the inner fork tube. Remove the dowel and take a tape measure and measure the distance from the Sharpie mark to where the dowel starts to get wet with oil(like a dipstick on a car). The distance should be 166mm(6 1/2"). It's better to slightly underfill than to overfill as more oil means more pressure in the forks which can blow the fork seals, and you don't want to have to change those out. If you have too much oil in, take a Turkey baster found at any grocery store, and remove a bit of the oil till you get the correct amount.

Then just put your fork springs in with tighter coil windings on top, and the spacer and spring seat(looks like a big washer). Then put the fork top cap screw back on with some steady pressure on it. Be careful here, because if you aren't you can crossthread the top cap. I've found it's easier to do this job with the correct 22mm 6 point socket, than with a wrench(spanner for you english types).

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