should i replace fork seals

[niko]

i have an 85 gs550l that i am reviving, and my question is... should i replace the fork oil seals on g.p.? one of the dust seals is in bad shape so i would like to replace that, but i cant see anything leaking out of the forks, so should i replace them all while i am doing the one or am i asking for trouble by messing with what aint broken?

thanks for your opinions

[Steve]

It is quite possible that you don't see anything leaking because there is nothing in there. :shock:

I had that situation several years ago when I got a 'new' bike. I did not change the seals on the first go-round, I just drained what little oil there was and replaced with the proper amount of fork oil. Considering that I only drained a total of about 2 ounces of oil, then added 10 ounces to each leg, the difference in performance was phenomenal. \\/

My suggestion would be to drain the existing oil (if any) refill with the proper amount for your bike, then see if you have any leaks. That will determine whether you need to change the seals. Eventually you will probably have to do it anyway, but this will at least assure you that you have the proper amount of fluid in there.

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[lurch12_2000]

It is quite possible that you don't see anything leaking because there is nothing in there. :shock:

I had that situation several years ago when I got a 'new' bike. I did not change the seals on the first go-round, I just drained what little oil there was and replaced with the proper amount of fork oil. Considering that I only drained a total of about 2 ounces of oil, then added 10 ounces to each leg, the difference in performance was phenomenal. \\/

My suggestion would be to drain the existing oil (if any) refill with the proper amount for your bike, then see if you have any leaks. That will determine whether you need to change the seals. Eventually you will probably have to do it anyway, but this will at least assure you that you have the proper amount of fluid in there.

.

I just changed my oil from 20w to 10w fork oil. When I drained it out I measured and got just under 8 ozs out of each(took 10 minutes each and some pumping of the front end) and filled each with 8 ozs of new oil.
Last year when I changed it I didn't measure what came out but put exactly 8 ozs of 20w (wanted to try heavier) in each.
Now with the 10w I have a softer ride with what seems to be less jitter in the front end.
My question is what bike do you have that takes 10 ozs in each fork? and also, I put a little air?? in to raise the front about 1 inch. I do have 2 1/4" spacers in each tube that the PO had put in. With or without air, when I sit on it it will compress 1".

[80GS750]

whats the best way to add oil???

do you have to remove the caps or can you pull one of the filler port thingies off and fill it through there???

[lurch12_2000]

whats the best way to add oil???

do you have to remove the caps or can you pull one of the filler port thingies off and fill it through there???

What's a filler port thingy?
I take my caps(3/4" open end wrench) off to make draining easier and then use a small offset funnel to pour a pre-measured 8 ozs from another cup. I don't pour from the bottle directly, otherwise I might put too much in. I drain and fill the forks one at a time so the bike's front end doesn't collapse on me and fall off the centerstand(I block the rear wheel too). Others will tell you to measure the fill level with the springs out to get the more accurate read and syphon off any excess.

[Steve]

My question is what bike do you have that takes 10 ozs in each fork?

That was in my Kaw Voyager 1300. Actually, I think the book called for 10.8 ounces, I was just putting down basic numbers for illustration.

The fact remains...not much came out, a LOT went in...performance improved.

And, I agree with your choice of thinner fork oil. Previous owner of my Wing installed Progressive fork springs and 15w oil. It was hitting expansion joints hard enough that my wrists hurt at the end of a day-long ride. I changed to 10w oil and like it much better. 8-[

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[80GS750]

i have little nozzles for air so i can put air in each tube....

thats what i meant by filler port thingy

ill just take the caps off and do it that way