fork seal question

[sstein]

I purchased my 02R three years ago with 14000 miles. At that time, three was some dried oil on the back of the left fork tube, suggesting a leak. I cleaned it off and left it alone. There had been no further leaking until this past week. Took her out for her 2014 inaugural, and plenty o' oil started spilling out from around the left dust seal.

Obviously I plan to replace both seals, but I was just wondering if anyone knows why the leak would be quiet for two years then start up again suddenly.

[billbeemer]

the seals will harden, then leak. i've had problems with my tubes leaking. after putting about 4 seals into the right slider, i discovered some small pits in the chrome on the slider. now i just let it leak...............i'm softly looking for sliders on beemerboneyard.

[sweatmark]

SEARCH for CycleRob's discussion re: fork seals and sliders.

Since I have the extra 90 seconds to do so right now...

http://www.r1150r.net/board/viewtopic.php?f=2&t=17579
http://www.r1150r.net/board/viewtopic.php?f=2&t=25511
http://www.r1150r.net/board/viewtopic.php?f=2&t=30783

Ok, so that took maybe 2 minutes, including this sentence.

[sstein]

Thanks. Thanks for the links, Sweatmark. And thanks for including your search time. Learnt that from Google did'ya?

[sstein]

I looked at a lot of threads on this topic and there is at least one link that shows how to replace the seals on the 1150r without removing the front wheel. Is that realistic , or does it have to come off ?

[AZBMWRIDER]

I don't know if it can be done or not, you have to remove the caliper and axle, plus the fender and lower fork brace .

The wheel is pretty much off at that point, except for the opposite caliper .

[billbeemer]

absolutely doesn't require removing wheel! loosen top nut on slider, compress under triple-tree and lift slider straight up out of tube. seal is readily accessable for replacing. i siphon fork oil out and refill with 400ml of 5w or 10w fork oil. remember, the oil is only to lube the sliders, doesn't perform any damping. dont forget to remove small allen screw, then on reassembly of slider, tighten allen screw when slider is in position to retighten top nut on tree. easy, peasy........

[MarkShelley]

Did it on my GS without removing wheel.
I bet if you do this regularly you could get it down to about 10 minutes a side!

[sstein]

GREAT! I was SO not looking forward to having to remove the front wheel. Thanks!!

[sstein]

Hey Billbeemer - I now have all the new stuff I need to do this job. Just a quick question for you and/or MarkShelley:

loosen top nut on slider, compress under triple-tree and lift slider straight up out of tube.

It appears to me that if I compress the slider under the triple tree and lift, won't the slider extend right back up to the triple tree where it started? Will I be able to redirect the slider past the triple tree and out?

[MarkShelley]

The following is from a guide on the ukgser website which I suggest you join as the advice on there is the best anywhere for maintenance tasks.

Remove plastic cap on top of fork
Place a 22mm spanner on the flats at the top of the leg , under the top yolk.
And the 14mm socket onto the top nut. And undo the top nut.

With the nut removed, push the fork slider down and out of the top yolk.
The front end will be all sloppy, allowing you to push the bars around and out of the way, and the front wheel can be moved in any direction for conveniance.

Pull the fork slider up and out of the stanchion. Wipe the leg as it's removed, as it will have oil residue on it.

Prise out the dust cover - These can be split and deformed, so look before doing the job and have a new one ready if needed.

Underneth you'll see the seal circlip. Prise free with a small screwdriver.

With a seal puller, or similar instrument, pullout the old seal. This is easiest done with my puller by pushing the fork leg as far forward as you can . Remember, the front wheel can moved to almost any position.

There is a washer under the seal. Pick it out,and clean it
Locate the new seal in place with your fingers, you can push it home a fair way to start it off

Then with a correct sized socket ( i use a 1" 3/8ths) you want it to run around the outside of the seal, but be small enough to fit inside the slider lips. Fit an extension bar onto the socket, and tap home the new seal.

Refit the circlip .
Refit the dust seal, just a push fit.

Then with a 3mm allen key, undo the small air bleed bolt on top of the fork stanchion and remove it,making sure you don't lose or damage the "o" ring on the bolt

Push the stanchion carefully back into the slider -remember the front wheel forks can moved around for the best position

Then pull the stanchion back up, so it's in line with the top yolk, in the same position where it will be when it's in place - Now keep the stanchion in place, and replace the air vleed screw.

Now position the fork stanchion back in place in the top yolk, and refit the nut.

Hold the stanchion with the 22mm spanner and do up the 14mm nut, replace the top yolk plastic cover. Job done.

[sstein]

Thanks MarkShelley. Very helpful.

[billbeemer]

yesterday, i had a used, low mileage front shock installed on my r1150 w/36k miles. the guy shimmed it with a washer on top for more spring preload. two advantages, one is bike is infinitely more stable, two is stanchions don't dip to point of scratches on my tubes, so i'll put another seal in and hopefully it will stay dry. live and learn..........

[sstein]

How much for and what brand of shock did you have installed?
BTW, you all were spot-on. Did not have to remove wheel to replace fork seal. Easy peasy.

[billbeemer]

i bought an oem from ebay for $110 that claimed 5k miles. i trusted the guy, and the shock works great. i am a country boy and the idea of spending $1000 on new oem shock or ohlins etc is foreign to my mind. jesus, it's a shock! plenty of used oem stuff out there from guys installing ohlins etc who disagree with me. one man's loss, another man's gain.

[CycleRob]

Getting back to the original topic of this post . . . fork seals . . . I do NOT recommend changing the seals without doing a complete fork slider removal from the bike to drain and solvent wash out the old oil and dark gunky sediment caked in place on both fork slider's internal bottom surfaces. Even if you only replace the one leaking seal, remove and drain/flush out the non leaking fork tube and replace that oil too. A quick-n-dirty job gets you a shorter quick-n-dirty component lifespan.

Just weeks ago I "helped" my good friend and fellow patriot CaptianCable replace his fork seals and top bushings on both the R850R's forks, so I know of this gunk I speak of. The brakes, brake lines, wheel, fender, fork brace and fork tubes were removed. After trying room temperature removal, seal removal was made much easier by using a heat gun on the slider OD where the seals are, with the chromed fork tube removed. Heat to just before the paint blisters and the residual oil smokes. This bike is a `98 model, so it was a worst case scenario for the frozen-in-place seal removal.

Fork seals get ruined by dirt and bugs that smash deposit and/or stick themselves onto the chrome fork tube surfaces. The seals then mostly wipe away those deposits, but a very small amount will eventually get past the 1st and 2nd sealing ribs of the fork seals that slide on that dirty chrome surface dozens of times every mile, even on "smooth" road surfaces. That dirt can also scratch the chrome surface of the fork tube when the suspension works, until it is ejected either up back out to the roadside or down into the oil supply in the fork. That is why you should remove the non leaking fork tube for kerosene type solvent cleaning and new fork oil. Think about sand in your bathing suit and act accordingly.

[captaincable]

Thanks again Rob for the help on the seals , s.s. brake lines and shocks on my 1997 R850R . The hardest part on the fork seals was taking off the old parts on the bike frozen bolts and screws, After that the forks were a breeze under Robs guidance and help or should I say I was helping him
Will take some pics and post and maybe Rob can give some pointers in his informative style. Thanks for all the input from the members here, always interesting searching the threads.With the above projects long overdue the bike is riding , stopping and handling well.
Mike
BTW Rob is right about cleaning out the forks lots of gunk in the bottom of the tubes, plus he honed the sliders with a stone it worked great no "catching" the new seals with rough spots above the surface.

[CycleRob]

To clarify, the ultra fine knife honing stone was used to hone away the remains of tiny rust pits that were removed by an industrial grade razor blade, skimming rapidly over the top 4 inches of the fork tubes at a very shallow ~5 degree angle. That is where the rust pits were, the place where the seal would go to on a very big downhill bump, with a passenger on board. The rectangular honing stone's "grit" is so fine it almost feels like a heavy piece of grey chocolate. When stroked rapidly on the chromed surface, it did not scratch or scuff the shiny chrome surface. It made it shine, like it should. You could hear the sounds of those pits being ground down, then disappear.
Every time I see rust pits on the upper part of the front fork tubes it really bothers me. It identifies an owner that 9-out-of-10 times was not even aware that the fork tubes are a serious, regular maintenance item. The damage can be expensive to repair, with the majority of the cost being just the parts! It's in the idle time off-season when those tiny droplets do their corrosion, usually reformed repeatedly from temperature swing induced condensation. That's why either thoroughly car waxing or a wipe down with an oily rag on the chrome surfaces you want to save is necessary if your bike is not stored in a climate controlled living space. If you only have the time or motivation to clean only 1 simple thing on your bike, the entire seal travel area above the fork seals should be it! It's the single most easily damaged part, the most neglected/overlooked part and the most unnecessary, most easily avoidable, big repair cost. It is also what should be the first thing you very closely inspect, on the bike you want to buy.

[billbeemer]

so after replacing my front shock with a used one off this forum and adding a washer for preload, my fork seal no longer leaks!! i'm very happy...............