The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: tagordon on July 27, 2007, 09:14:29 PM

Title: Fork Seal leak
Post by: tagordon on July 27, 2007, 09:14:29 PM
I noticed my leaky fork appears to be getting worse. I do not notice any symptoms aside from the fluid on the fork. Any one that has done a replacement of the seals. Anyone that has replaced the fork seals please respond. As with the major list of winter work I plan for bike. I am hoping to put this off till then. Or should this be addressed now. Please advise me as to what behavior I should look for to alert me immediately repair.

Troy

PS. I wonder if me locking up the front brakes the other day aggravated the leak I  already had. I locked both brakes & went down to prevent slamming into the side of a car. They did not look & pulled in front of me from a side street.
They took off & I or none of the witnesses got the license number.
I will most probably recognize the driver if I ever see him or the car again.
Hope I don't actually. I will need to repay him for some bruised ribs & road rash.
Title: Re: Fork Seal leak
Post by: nhmaf on July 27, 2007, 10:21:04 PM
The seals aren't too expensive - I'm not sure which model year your bike is, but be sure you get the
right ones for your model year (I think the pre-81 forks used a different size seal).   Always replace
both seals when you're at it.

You'll also need to get a fresh container of fork oil.  You'll need a syringe or some sort of measuring cup
(that you will never use for cooking again) and a narrow funnel to put the proper amount of fork oil in.
I usually replace the felts in the slider covers, but you don't usually need to.  

You should also get new crush-washers (aluminum and/or copper ones) for the
drain bolts and for the large bolts that are on the bottom end of the sliders that bolt into the damper
assembly inside.  The crush/sealing washers are very inexpensive, but if you try to reuse them and
they don't seal right (sometimes they do, sometimes they don't when re-used).  You'll have to do it all
over again.   It is also a good idea to clean and regrease your front wheel bearings as you'll have the
wheel off, and if you haven't changed your brake fluid in a couple years, it is a good time to do that too.

Many here can help you with the tools and procedures once you get close to being ready.   If it isn't
leaking too badly, you might put off working on it for awhile, but be aware that your handling will
progressively deteriorate, and if the seals completely go and you have no oil left, things could get
a bit scary under high speed or emergency manuevering situations.    

glad that you are OK and managed to avoid serious injury & damage with the clueless cagers !
Title: Re: Fork Seal leak
Post by: msbuck on July 27, 2007, 11:00:40 PM
I've got the leaky fork seals as well.  Although mine is bad enough that I'm seeing oil on my front tire.  :o  We've done Graham's 1981 R100, but his are somewhat different.  I've got the seals ordered and plan on doing this job early next week.  Any helpful advice on getting the sliders out on my 1984 R65?  We think we know how to proceed, but thought I'd check and see what helpful advice you R65 gurus could lend me.  

Thanks!

(I need to get his completed before the great "Adventures in Willville" weekend!)  :D
Title: Re: Fork Seal leak
Post by: airhead on July 28, 2007, 12:25:59 AM
While you have everything apart, if you don't already have them, consider getting gaiters and fitting them as well. They go a long way to protecting the sliders and extending seal life (as long as the sliders aren't bent in the first place).

Bill....................;-)
Title: Re: Fork Seal leak
Post by: Jon_P on July 28, 2007, 07:59:17 AM
i found that some of the smaller leaks are caused by dirt and stuff in between the seals and the fork tube. i have taken some small wire and gently run it around the between the seal and fork and then check it a day later. only once did i have a seal that was leaking real bad, but most of the time this helped if not stopped the small leaks.
Title: Re: Fork Seal leak
Post by: MrRiden on July 28, 2007, 11:39:52 AM
Not really seal related but while your at it
http://www.w6rec.com/duane/bmw/forktool/index.htm
Ive been wanting to check my forks with some sort of jig. anyone here ever try this?
rich
Title: Re: Fork Seal leak
Post by: tagordon on July 29, 2007, 03:06:01 PM
Jon
Please give more detailed info regarding the wire cleanout procedure you mentioned. I will give that a try & see what happens. If it helps, great. If not, no loss. Other than the time involved.

Thanks
Troy
Title: Re: Fork Seal leak
Post by: msbuck on August 03, 2007, 07:43:18 PM
OK, we've replaced the fork seals and will be putting everything back together in the morning when it's cool out (90°F plus all week, geez!).  We have a plan for tightening the lower bolts that holds the slider(yoke) to the fork(stancion), but I was wondering if anyone had any neat tricks for this procedure they might want to share with me.  :-*  

My sliders are different from Graham's '81 R100 in that the front axle runs below the bolt while Graham's has the front axle out in front so it doesn't hinder getting to the bolts.  Gettting these suckers tight and torqued in might be challenging...  
Title: Re: Fork Seal leak
Post by: Ed Miller on August 04, 2007, 08:14:05 PM
Quote
Not really seal related but while your at it
http://www.w6rec.com/duane/bmw/forktool/index.htm
Ive been wanting to check my forks with some sort of jig. anyone here ever try this?
rich

I've done it, though I followed the much more detailed procedure in the article by Randy Glass, also on Duane's site.  There are several R65 peculiarities as you might imagine but it's not too tough.  My forks were not in the plane, and when I tried to straighten them using a long board and a ratcheting tie down I bent the board a lot but the forks wouldn't move.  I didn't know that I was supposed to remove the upper clamp.  The other BMWs just have a stamped metal plate for the upper, unlike our sturdy strong cast ones, so if I just removed it and was able to bend the lower one, the upper one wouldn't fit.  So I ended up loosening all 4 clamp bolts a bit, and applying the pressure via the board until the forks were in a plane.  Then I tightened the clamp bolts, undid every thing, and had to do it again a couple times until I got it right.

Luckily my forks were parallel, so I didn't have to try to adjust that.
Title: Re: Fork Seal leak
Post by: Ed Miller on August 04, 2007, 08:18:56 PM
Quote
OK, we've replaced the fork seals and will be putting everything back together in the morning when it's cool out (90°F plus all week, geez!).  We have a plan for tightening the lower bolts that holds the slider(yoke) to the fork(stancion), but I was wondering if anyone had any neat tricks for this procedure they might want to share with me.  :-*  

My sliders are different from Graham's '81 R100 in that the front axle runs below the bolt while Graham's has the front axle out in front so it doesn't hinder getting to the bolts.  Gettting these suckers tight and torqued in might be challenging...  

Do you mean the bolts, one per side, that bolt up into the absorber inside the stanchion?  If so, I'm pretty sure I did that with my axle out.  If the absorber turns inside, you have to hold it in place with a 13mm socket on a long extension from the top.  Or am I completely confused?
Title: Re: Fork Seal leak
Post by: NC Steve on August 04, 2007, 08:26:45 PM
Quote

(I need to get this completed before the great "Adventures in Willville" weekend!)  :D

Yes indeed, Aida, yes you do. Everyone's gotta get their R65s in top shape for the trip.
You've got your fork seals, I got my carbs sync'd and valves adjusted today, and John's changed his oil and bought a new helmet.

(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi146.photobucket.com%2Falbums%2Fr261%2Fsteve2371%2Ff920_1.jpg&hash=642cea3a54060fcca2fe22e5c5bf25e890f140ad)

Look out, Willville!!  ;)
Title: Re: Fork Seal leak
Post by: tagordon on August 05, 2007, 09:12:29 AM
Does the Mohawk help with cornering? As in airfoil.
Title: Re: Fork Seal leak
Post by: NC Steve on August 05, 2007, 09:31:58 AM
He refuses to discuss it, but it's my understanding that John is conducting exhaustive aerodynamic research at the top-secret testing facilities hidden deep within the deserts of South Carolina... ;)
Title: Re: Fork Seal leak
Post by: msbuck on August 05, 2007, 07:51:14 PM
Ed,  yes you're right on.  We finally figured out the part about coming in from the top to steady the absorber.  I went back through the old threads and found a discussion about it and also on the R65 FAQs by Noemi Berry.  We were trying to put pressure on the springs to get the bolts to tighten, but couldn't make it work.  We're all done putting the forks back together, but it gets so HOT   in the afternoon we called it quits again till morning.  Then we'll finish up with the oil and putting the fender, wheel and calipers back on.

We also retorqued the heads and adjusted the valves.  Getting ready to go!!  Can't wait to see John's new look!!  ;D
Title: Re: Fork Seal leak
Post by: tagordon on August 07, 2007, 08:54:28 PM
Please post links to all available info regarding replacing fork seals. Also any notes you feel helpful. I will put together a printout that I can study to prepare for the hands on "test".
I still want to visit the Indy BMW shop for an explaination to the phone conversation. I was told they would replace the seals off the bike for 70 - 100USD.
But if I deliver bike & they do it all then several hundred USD.
Is it that much labor?
Title: Re: Fork Seal leak
Post by: Bob_Roller on August 07, 2007, 09:08:27 PM
It depends on the shop labor rate, to remove and install the forks, you can expect a 2 hour labor rate. Here in the Phoenix area the going rate for shop labor is around $90-95 an hour. It's really not a difficult job to replace the fork seals, the last time I did it about 2 months ago, I think I had both forks done in about an hour and a half, with the forks off the bike already.
Title: Re: Fork Seal leak
Post by: msbuck on August 07, 2007, 10:41:10 PM
http://www.nebcom.com/noemi/moto/r65faq.html#THINGS_TO_KNOW

http://suraklyn.com/yabb/YaBB.pl?num=1182700260

If you take the forks off your bike and take them to your shop you could cut out a big portion of the labor bill.  It's not too tough a job, though, once you figure out the key differences for our R65s.  The above links should give you a pretty good idea of what to expect.