fork joints R80GS leaking where to change them
 

Hi, I have a BMW R80 GS Paris Dakar from 91, I've started a 6 month trip, I'm now, after 2 weeks in Latvia. Both my front fork joints are leaking sligntly.... I changed them befor I left, 3000km ago! Bought 2 on ebay, not genuine BMW, I don't know which they leak. Anyone could suggest me where to go to change them? Next I will go a couple of days in Finland and then 1 month in Russia befor Mongolia and the stans..

thanks in advance for your help

zimiontheloose.ch | Rock'n'roll Motorcycle Adventure!

I know an awesome place in Holland to change them ... but he would probably recommend you change the whole forks to something better rather than just the seals.

You could go to a BMW dealer, but you will probably have to wait to get the parts sent over from Germany. I wouldnt be sure that BMW motorrad dealers in Latvia or Estonia will have seals for 20 year old bikes in stock. Maybe you need to get someone in CH or DE to buy you some and just get them sent to you in the baltics. There are a million shops selling parts for old BMWs in Germany. In the meantime, find a regular motobike shop so that when the seals arrive they can change them for you.

If the seals are leaking so early, there is also a risk the chrome on your fork sliders are badly scratched. It might be bad seals, but it also might be worn forks.

I would look on-line and find a dealer somewhere you expect to be in about a week and get them to order new, genuine seals for you and have them fitted/fit them yourself when you get there. You might want to check the condition of the fork tubes while you are at it, my '91 GS has done 250,000 km and the forks are still fine with only one seal replacement in that time so age and high mileage does not mean the forks have to be replaced.

my r80gs has now covered 100,000 miles (160,000km) and the seals are fine but I do replace them as a matter of course occasionally - but the sliders are still in excellent condition - Order the fork seals as already has been said from a bmw specialist , ie motoren israeli, motorworks etc and get them sent out to you - carry a spare set anyway - when you change the fork seals - after making sure the sliders are in good condition - ensure the right oil and exactly the right quantity is used as to stiff an oil or a slight overfill will make the seals leak quickly. Joergs from Germany has a good guide to changing the seals its a simple job that you could do yourself on a campsite in a couple of hours. Here is a link to doing the job properly Joergs R80GS Page hope that helps.

Hi thanks for your answers. So first the fork tubes are not damaged. Then about the oil quantity I sure I've put the right one 410 and 440ml, and had to mesure the height of the oil (I think it was 160mm) when fork is completely compressed, without springs inside. Then I add the springs (progressive springs from WIRT) and close the fork.
What was very very strange, is that the 2 inner 6 pan bolt on the top of the fork, were like half unscrewed after about 2000km! I saw it by chance and tightened them again, but I can't explain how it is possible that they were loose. Because I tighten them firmly when I did it the first time.

I know Joerg in person, he's living in Switzerland not so far from me, and I used mostly his weppage to prepare my bike for the trip. But the thing with the fork seals, is it's very very difficult to get the ring out, to access the seal, and we have quite some difficulties in taking this out, scratching a little the inner part of the fork. So I won't be able to do this alone with the tools I have with me.

I will try to order thoses.

Thanks
David

The seal is a standard industrial seal. I can't remember the size but it's usually printed on the seal (three numbers). It should be possible to get them a bearing-supplier or maybe at some mechanical workshop.


Oil level (BMW-springs):
Left: 410ml (470ml after disassembly)
Right: 440ml (470ml after disassembly)


The standard tool-kit contains all the tools to remove the inner-leg, it's a very simple construction.
If you change the seal without moving the inner-leg the risk of ruining the seal (or inner-leg) is huge!

http://www.actiontouring.com/pic/sim.jpg

thanks for your answer, what is the inner leg? I don't understand. I had to remove first the first the dust cap, then the difficult ring to take out, then there was a washer and then I could take out the seal.

Do you think I have to change the dust cap as well? Or it is reasable. I juste changed it when I left

The chrome/blank tubes:
http://www.actiontouring.com/pic/sim2.jpg


There is a bushing under the seal and if it's badly worn it can make the seal leak pretty fast, but they usually last for a long time.


If it looks good it's probably okay.

ok, thanks!!!

If you're replacing the seals, remove the bolt at the bottom of the leg so that the upper part (the shiny bit) can be removed by pulling it out sharply, past the seals and top bush. Then the best way to remove the metal circlip to access the seal is to drill a small hole (2mm) in the leg exactly opposite the circlip groove. With the chrome part removed, you should be able to see the groove easily and measure how far down it is. This allows you to push the circlip inwards with a suitable tool. Trying to remove it from the inside with something sharp is difficult. You can fill the hole up later with a dab of silicone. I have found a suitable diameter/length of PVC pipe usefull in driving in the new seal. Obviously the forks are off the bike and the springs removed. Don't mix up any parts.

The circlip is number 6, the bolt to allow the chrome part (upper leg) to be removed is number 10. The seal is number 4.

thanks for the information, I will see what can I do. I was not able to order them in switzerland to let them ship in finland, my dealer didnt have them in stock, so I will have to see in russia probably..

An easy way of removing the circlip - and I done it to mine recently was using two pointed picks (tools with pointed ends - look like dentistry picks) available cheaply from small tool shops - the set I have has a hooked point, a straight point, a 45 degree offset point and a 90 degree offset point - the whole set was only £3.00 and are really useful for many jobs but more so for helping removed circlips, spring clips and the like. The seal can easily be popped out using a flat blade screwdriver under its lower edge and levered over the top of the fork leg. Use the old seal to push the new one home.

I found 2 joints in Finland with the help of Capo Sakke!
Will go to a mechanic somewhere on the road in Russia