fork settings...

[80GS750]

ok guys, i have a 78 gs1000E

bike sat for years....

both seals leaked like crazy when i put oil in.. but they seem to be getting better... i ordered new ones already...

anyway, the rate feels ok, nice and soft, not too stiff, my problem is the sagg, i need to space them up about 1 1/2",

heres my measurements,

sitting on the centerstand, fully extended, i have 6 1/2" from dust boot to triple tree..... thats open tube available for compression...

sitting on the side stand, i have 4 7/8" left... wow

sitting up, no weight on it, not on any stands, i have 3 3/8" available

and with me sitting on it, i have 2 7/8" free...

it only moves about 1 1/2 to 2 1/4" when driving... it doesnt bottom out, it just seems to ride low in the front and i dont want the fender that close to my oil cooler

i want to put in a pvc spacer, and see how it rides then... what size do i need????

also, i put 15w oil in it, and it was way stiff, i drained half the oil out and it was pretty nasty, now it rides ok but im sure theres still some gunk in there....

i was thinking about seeing if i can put a spacer in, then swapping out the oil a couple more times to clean it up, the old seals seem to be coming back to life, if not, i have new ones coming to replace them....


any ideas, any help at all is appreciated!!!

-nate

[bonanzadave]

I filled my forks up with WD-40. Made two collection tanks by cutting down a couple milk jugs and taped them to the forks by the drain screws. Drained, pumped, filled....until the WD-40 started coming out clean. I let it sit and then pumped them dry. Put the Progressive springs in and a cup of 10w fork oil in each side. Works fine. I think you need new springs.

[80GS750]

i found this illustration....

is this how our forks work too???

[Steve]

If you have 6 1/2" fully extended, you want 5 to 5 1/2" with you on it. Since you now have 2 7/8", I would start with a 2 1/2" spacer. Place a flat washer between the spring and the spacer so the end of the spring does not chew away at the end of the plastic spacer.

You put 15w oil in and it was stiff. You drained half of it out. You still running half the proper amount of oil? That will do strange things for handling. Try 10w oil, but fill it to the correct level.

.

[Steve]

The diagram that was posted while I was typing my last response is apparently part of a sales pitch for some kind of sealed system. I don't know how much the oil is "contaminated" by exposure to air. I would think it gets more contaminated with the metal particles that result from wear inside the forks.

The basic operation is probably similar. Using this illustration, you can see why level is important. If you have half your oil gone, the piston will be operating in air, which offers virtually NO resistance. When you hit a bump, the piston will move down and hit the oil rather suddenly (kida like doing a belly-flop off the diving board), dramaticaly changing the damping response for the rest of its travel. It is far better to have the oil high enough for the piston to be constantly immersed, yielding consistant damping results.

[80GS750]

aaahhh i see

yea i was riding with half the amount....

i went and cut 1 3/4" spacers and am gonna put them in with the correct amount of oil

i also measured my springs... they are exactly 16 1/2" long just laying there out of the tubes... does this sound correct?

[80GS750]

ok, i put the correct amount of oil in each tube, 260ml, and i put in 1 3/4" spacers, and now she rides right, smooth, higher, and i can even tell my posture is better cause im not leaning forward on the bike as much...

wow... she only drops about 1 1/2" at most now when i take her off the forks...

i have about 4" of play now and she feels way better

the seals arent leaking, but they are old and i expect them to weep a little as i ride...

but at least all the gunk is out now..

the old oil came out pretty much black!