new fork seal leaking GS1100 GLZ

[gert du prez]

Hi,

After an unsuccessful replacement of my fork seals (well, everything was OK until the left fork started spitting out all the oil, even when the bike was parked for weeks in my garage), I read all the front fork posts on the forum,
and that is what I came up with:

- I DID use an air compressor (yeah, I know) to fill the forks with air...I was ignorant, once...

- I DID NOT clean the inner fork leg enough from rust and dents...

One of these, or both, is forcing me to replace the seal again.

I think I can handle issue n? 1 , but what is the best way to get rid of the rust/dents/pits of the inner fork leg ?

just rubbing it with steel wool ?
is there a product I can buy that can help me do the cleaning trick ?

thanks,

Gert

 

[chiphead]

Forget the air and get some progressive fork springs.

Rust, dents and pits on the fork tubes are bad news. I sanded and dressed mine and only got a season out of new seals. Wound up replacing the front end with an 1100E model that had decent fork tubes. There has been some talk here about filling in the dents and pits with JB Weld or similar then trying to get in nice and smooth. I'd look for new/used fork tubes in good shape.

 

[gert du prez]

the springs already look 'progressively wound up', although I think you mean something else ? is 'progressive' a brand name ?

 

[twr1776]

Unfortunately if your tubes too bad you will not be able to bring them back. I think the Leak Pruf Pro Moly brand seals are a little more forgiving than the OEM ones if you have some damage on the tubes. When you install either type be sure to put some fork oil on the seals and tubes before you slide the new seals in. Maybe post a picture here for opinions on if you can sand them out. I doubt steel wool will be aggressive enough if you have dings on the tubes. Progressive are here in the states and I would think they are available by you. The # 11-1107 is what you need in Progressive. Hagon also makes fork springs and they are made in the UK so you should be able to get them. I have not used the Hagon fork springs before but do have a set of thier rear shocks and they work well. Here are a couple of links for you.

http://www.progressivesuspension.com/prodSearchResults.aspx?yearID=1982&makeID=45&modelID=840

http://www.hagon-shocks.co.uk/FS_Apps_list.htm

 

[gert du prez]

If a used rubber seal looks intact, does that also mean that it IS actually intact ? or can it be the reason for an oil leak anyway ?

Why ?

Well, I have re-inspected the area of the front fork leg area that goes in the outer tube (down leg) and apparently the 'impurities' are only on the upper part (so not passing the rubber seal).

But what I DID found, was a rather large scratch on the inside of the lower leg, where the outside of the rubber seal is sitting (just below the metal clip that holds the seal in place...).

Is it possible that the oil was leaking via the OUTSIDE of the rubber seal, rather than via the inside which I was expecting ?

If not, then the air compressor blew the perfectly looking seal...

Any experience ?

I bought new seals, but before installing them, would like to know if I will not end up with the same problem...

thanks

g

 

[Macmatic]

From my understanding you CAN have a leak on the outside of the fork seal, between the outer fork tube and the seal. I'd correct the scratch you mention, clean your inner tubes up as best you can and try again with some Leak-Proof seals. I think it really depends on how bad your inner tubes are, can you feel pits or even worse protrusions when you run your nail over them?

/\/\ac

 

[gert du prez]

The dents and pits on the tube are ok as only situated above the part that goes into the leg...the scratch on the outside of the seal however is a big one (I guess I must have slipped with the chissel a long long time ago...)

How do you repair that ? can you fill it up with something ? what to use ???

 

[82Shafty]

http://www.thegsresources.com/_forum/showthread.php?t=135849&highlight=11-1108

See my posts under the thread above.

"Just in case someone wants to put progressive front springs on their '82 850GL, I used progressive p/n: 11-1108. There is no listing for the GL model on any of the progressive data sheets - just the G models, which use a different fork & stock spring than the GL.

The OEM stock GL springs measured 21" long & used a 3.1" long spacer under the cap.

The 11-1108 springs measure 20.75" long, and I used a 2.8" spacer to provide the required level of pre-load recommended by progressive (.75" - 1.0" of preload).
​

In addition, I installed new fork seals and replaced the "black" fork oil with nice new 15W oil - filled to an OEM level of 10.2" (260ml).

Seems to ride & handle much better, and the front end doesn't take a nose dive now when the front brakes are applied!

Hope this info is of interest to someone...

mike "

You can use 11-1107, but you will need to buy rigid pvc ( I used the electrical stuff) to have two 6.5" spacers.

 

[gert du prez]

the repair is done

the repair is done

Hi,

in order to close my 'issue'...

I bought some liquid sealer and sealed the deep screwdriver scratch on the outer ring (where the outside of the fork seal is sitting). I also cleaned the tubes, filled the forks with the right amount of oil, and HANDPUMPED the air in the forks.

Everything has worked out fine, no more oil leaking. So, what have we learned ?

- air compressor is good stuff (if you want blow up your rubber boat), but DON'T use it to fill the front forks...

- it is not always dents and pits on the tube that cause the leaking, in my case it was the scratch on the other side of the seal (probably caused when trying to pull out the old seal).

Now, I'm only waiting for my new front springs. I found some from WP Suspension that you can easily buy here in Belgium (97 EUR/pair),
item number for the GS 1100 L is : 9932.0212.B

 

[Don-lo]

Actually, a home air compressor (with tank) is the perfect way to set your air pressure. You just need to set the pressure in the tank to the desired level, not run it up to high pressure. I run 12 or 18 psi, depending on whether the fairing is on the bike. Thus, when you connect the forks to the tank, they will perfectly equalize to the tank and to each other. Just make sure to pull the nozzle quickly off the nipple so you get the same kind of "pop" each time.