Fork Oil!

Mzokk

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I've just noticed my right hand fork leg is leaking a bit of oil. I may as well change the fork oil when I'm changing the seal. The manual recommends "BMW telescopic fork oil" Has anyone any Idea what weight this oil is?

Ta :)
 
Em! The stuff that’s squirting out seems thicker than normal fork damping oil. But i'd like to put in the correct weight as there is a fair bit in each leg…. 470cc's of the stuff! :)
 
Found this on Adv rider. Will try and take pics when I'm having a go at this. Ta :)


Oilhead fork oil is 10.0 Wt

--------------------------------------------------------------------------------

Great advice, that matchs what the tech said at the local BMW dealer... Except!

Step-8)
Either suck out, and replace the fork oil (470cc of BMW 7.5Wt.) or guess at how much came past the leaky seal, and squirt that much in there. Error on the skimping side.

The manual says:

Telescopic fork oil – approved grades BMW telescopic fork oil


BMW Fork oil: 7.5 Wt
BMW Telescopic Fork oil: 10.0 Wt


Airhead fork oil is 7.5 Wt, but Oilhead Telescopic is 10.0 Wt.


Patrick
Live Long and Ride



Quote:
Originally Posted by kevbo
Here is a quick procedure, doesn't even require removing front wheel. You do have to work inside the beak. I'm 6'5" and if I can get my big hands in there, anyone should be able to.

Sorry, no pictures, I did this in the dark, and it was windy, and didn't want delays adding to the grit.

Changing a 1150GS fork seal should be a 30 min. chore the first time, and maybe only 15 minutes the second time. Bout $30 in parts including a quart of BMW fork oil.

Step-0) put bike on center stand.

Step-1) Remove the cable clip which is around the top of the fork leg. That is not a normal zip-tie, don't cut it. It is reuasable, there is a small release tab. This is perhaps the most time consuming part of the job.

Step-2) Pry out the cap on the top of the triple-clamp. I used a pocket knife.

Step-3) Hold the fork leg with a 22mm open end wrench, and use a 14mm socket to remove the nut that was under the step-2 cap.

Step-4) Push the fork leg down, then bring it forward. Have a rag ready to put under bottome end which will be dripping oil. Then pull the leg upward and out. Be careful not to drop or scratch it.

Step-5) Pry the dust seal out of the slider. knife blade again to start it, small screwdriver to finish it.

Step-6) Remove the small wire clip which holds the seal in place. Small allen wrench makes good tool. DON'T drop it down the slider. Note that the seal is positioned so that the garter spring is visible.

Step-7)pry the old seal out. Screwdriver job. Use twisting motion rather than prying on edge of slider.

Step-8)
Either suck out, and replace the fork oil (470cc of BMW 7.5Wt.) or guess at how much came past the leaky seal, and squirt that much in there. Error on the skimping side.

Step-9)Install new seal, I used a 5/8" fender washer on a long bolt to push it home. Hand pressure was enough, no need to pound. Garter spring goes on top side.


Step-10) Put everything back togethor. Don't forget the snap ring.
Locktight on the top nut., torque to 45 Nm (~32 lb-ft) Yer done.
 
I have always removed the fork and drained it completely of the remaining oil - and the accumulated sh1t - before reassembly.

Not that difficult a job and a lot easier to remove and refit the seals away from the bike.

Iain
 
Tried the "keep the fork on the bike method" today. 10 min job to change the seal. But of course couldn't drain the oil.
Suprising how loose the front end is once the fork tops are released.
 
The quick method above has worked like a treat up to point 7.

Got the forks out and dropped them off at Brian Parsons to get them straightened after my Morocco prang. I was surprised (and a little shocked) to see how banana shaped the left fork was, altho' managed 3500 miles with it with no apparent problems.

Back in the garage and got dust cover and garter clip out no probs...but the seal refuses to budge despite much screwdriver prying. I am a little worried about damaging the washer beneath or the slider...but in any case the seal resists my levering.

(I have also put in too much fork oil I think...however the turkey basting pump should sort that problem out!).

So...any tips on how to get the seal out gratefully received. Thanks

Simon
 
Good to see old threads resurface after a year!!! My seals were difficult to pry out. I ended up removing the fork legs completely (as I wanted to paint the fork lowers and fork bridge) and I used a bit of perspex screen edge to protect the finish on the fork stanchion and pry-ed the seal up while playing a heat gun round the top of the stanchion. I put the replacement seals in the freezer for a while prior to fitting and heated the tops of the stanchions. I pushed the seals in with a bit of inch and a half plastic pipe. They just slid straight in. No more problems since. :)
 
Thanks Mzokk...good threads live on for ever!!!

I am fighting hard not to remove the forks but glad I am not the only one to have struggled... and a bit nervous about a heat gun so near the tank!

Guess I'll keep on prying

Simn
 
simondippenhall said:
Thanks Mzokk...good threads live on for ever!!!

I am fighting hard not to remove the forks but glad I am not the only one to have struggled... and a bit nervous about a heat gun so near the tank!

Guess I'll keep on prying

Simn

I'll second that, it's a job I need to do this weekend, cheers everyone.

Simon
:clap
 
Job done, elected to take fork off, seal came out ok, and new one went back in fine thanks to the special tool lent to me by Roy of RGM motorcycles, what a bloke! That said could of bodged it but having the kit makes things easy.

:thumb
 
It worked fine for me doing it the '10 minute way'. Removed the excess fork oil I overdid using my youngest son's old Calpol syringe (he's 11 now so won't need that) and pried the seal out OK. Picked up the nicely straightened fork legs - well worth £20 the pair!

Took the tip of putting the new seal in the freezer (shrieks from SWMBO) and blagging her hairdryer (even more shrieks) to heat the fork in situ.

So the seal went in OK despite a few scary moments when the metal springy coils came out of the seal. Did it without any special tools (wish I had it).

Off down the road, no evidence of leaks so a successful mission. Took lots longer than textbook...probably because I really did not want to screw up. Think I should be a lot quicker the next time. And working inside the beak is a bit of a pain...how much work is involved in reoving the forks as a whole? (Learning for next time)
 
Not much extra work really, I only had to replace one seal so decided to remove the leg, just gives you more room. Also have not had to remove fork leg or dismantle them before so was useful experience. Will need to remove fork legs some other time to paint sliders.

Haynes provides a reasonable explanation of the procedure so if you don't have one would reccomend that you get hold of a copy.

:beer:
 
Found this on Adv rider. Will try and take pics when I'm having a go at this. Ta :)


Oilhead fork oil is 10.0 Wt

--------------------------------------------------------------------------------

Great advice, that matchs what the tech said at the local BMW dealer... Except!

Step-8)
Either suck out, and replace the fork oil (470cc of BMW 7.5Wt.) or guess at how much came past the leaky seal, and squirt that much in there. Error on the skimping side.

The manual says:

Telescopic fork oil – approved grades BMW telescopic fork oil


BMW Fork oil: 7.5 Wt
BMW Telescopic Fork oil: 10.0 Wt


Airhead fork oil is 7.5 Wt, but Oilhead Telescopic is 10.0 Wt.


Patrick
Live Long and Ride



Quote:
Originally Posted by kevbo
Here is a quick procedure, doesn't even require removing front wheel. You do have to work inside the beak. I'm 6'5" and if I can get my big hands in there, anyone should be able to.

Sorry, no pictures, I did this in the dark, and it was windy, and didn't want delays adding to the grit.

Changing a 1150GS fork seal should be a 30 min. chore the first time, and maybe only 15 minutes the second time. Bout $30 in parts including a quart of BMW fork oil.

Step-0) put bike on center stand.

Step-1) Remove the cable clip which is around the top of the fork leg. That is not a normal zip-tie, don't cut it. It is reuasable, there is a small release tab. This is perhaps the most time consuming part of the job.

Step-2) Pry out the cap on the top of the triple-clamp. I used a pocket knife.

Step-3) Hold the fork leg with a 22mm open end wrench, and use a 14mm socket to remove the nut that was under the step-2 cap.

Step-4) Push the fork leg down, then bring it forward. Have a rag ready to put under bottome end which will be dripping oil. Then pull the leg upward and out. Be careful not to drop or scratch it.

Step-5) Pry the dust seal out of the slider. knife blade again to start it, small screwdriver to finish it.

Step-6) Remove the small wire clip which holds the seal in place. Small allen wrench makes good tool. DON'T drop it down the slider. Note that the seal is positioned so that the garter spring is visible.

Step-7)pry the old seal out. Screwdriver job. Use twisting motion rather than prying on edge of slider.

Step-8)
Either suck out, and replace the fork oil (470cc of BMW 7.5Wt.) or guess at how much came past the leaky seal, and squirt that much in there. Error on the skimping side.

Step-9)Install new seal, I used a 5/8" fender washer on a long bolt to push it home. Hand pressure was enough, no need to pound. Garter spring goes on top side.


Step-10) Put everything back togethor. Don't forget the snap ring.
Locktight on the top nut., torque to 45 Nm (~32 lb-ft) Yer done.

Thanks for that . Going to have a go and do my 1150GSA as mentioned here here

Watched this vid too


 
Flip me that's a blast from the past!! I haven't had to replace fork seals again either in the intervening 75,000 miles!! and 20 years!!
 
I have always removed the fork and drained it completely of the remaining oil - and the accumulated sh1t - before reassembly.

Not that difficult a job and a lot easier to remove and refit the seals away from the bike.

Iain
Haha... Yip and this and Arseys thread make it sound way more difficult than it is...😆 Take the fecker off and not even a damping rod to loosen...😄
 
Haha... Yip and this and Arseys thread make it sound way more difficult than it is...😆 Take the fecker off and not even a damping rod to loosen...😄

You know how much the yanks like to pontificate over everything and make the most simple things into a drama :D

10 minute job to change a fork seal. Another 5 minutes to change fork oil :D

There’s a “how to” in the oil head tips and info section .. pictures have disappeared but you don’t really need them to work out https://www.ukgser.com/community/threads/fork-seal-fitting.62436/
 
Thanks for that . Going to have a go and do my 1150GSA as mentioned here here

Watched this vid too


I’ve replaced the seals a couple of times on my 1150GS. First time I removed the front wheel and slide the lower fork leg off, leaving the upper in place and changed the seals and oil. The second time I followed the ‘Steptoe’ method, which was quicker but neither method was difficult. I found a piece of indoor plumbing pipe that was a perfect size for pushing the new seals into place, it now lives in my ‘bike’ tool box.
 


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