Fork seal time

[Hadabadachada]

2013 R1200R 

 

So I’ve noticed dirt and grime build up on my forks. I wipe it off and it’s back after not too long. A little bit moist, I’m pretty sure my fork seals have some scratches, and fluid is creeping by.

 

was gonna replace the seals, then I start looking at the schematics. 
im wondering if this will be as easy as on the oilhead.

 

I was going to say, I don’t see any screw holding the stanchion in on the bottom. 
I think that’s how I got the one on the 1100 out. 
 

im wondering what the process is, before I just get balls deep and stuck, ayo

[dduelin]

Mine does that from time to time and three times ‘round the offending fork tube with a Sealmate tool takes care of it. 

[dirtrider]

13 hours ago, Hadabadachada said:

2013 R1200R 

 

So I’ve noticed dirt and grime build up on my forks. I wipe it off and it’s back after not too long. A little bit moist, I’m pretty sure my fork seals have some scratches, and fluid is creeping by.

 

was gonna replace the seals, then I start looking at the schematics. 
im wondering if this will be as easy as on the oilhead.

 

I was going to say, I don’t see any screw holding the stanchion in on the bottom. 
I think that’s how I got the one on the 1100 out. 
 

im wondering what the process is, before I just get balls deep and stuck, ayo

Morning  Hadabadachada

 

It's not real difficult but a BMW service manual would be a BIG help. 

 

Obviously remove front wheel, ABS sensor, front brake calipers.

 

If you can get enough front height (or hang wheel off of the front of a lift table) you can pull the lowers off of the uppers.

 

Or you can just  remove the upper tubes  upper nuts then rotate the upper triple tree & work the upper tubes out. (if you remove the upper tubes you will have to find a way to suck the fork oil out).

 

New fork oil amount is 640ml of 10 weight fork oil. 

 

I have only done one camhead 1200R & on that I  removed the entire fork on each side as BMW service manual says to not slide the entire  upper tube through the new seal as the sharp edge of the vent hole can damage the new seal. I pulled the upper tube through the old seal to be able to easily remove the seal but I slid the tube back in before installing the new seal. 

 

On removing the forks, I removed the lower fork bridge pinch bolts then drove a plastic wedge into the pinching gap to sort of open the gap so the fork leg would slide out without scratches or damage. Same with re-installation.

 

Pinch bolts get torqued to 25nm in3 steps each alternating between bolts.

 

Upper fork tube top nut gets torqued to  40 nm. 

 

One gotya to pay attention to is to remove the front wheel speed sensor before work as it is easy to damage.

 

Personally, I would first try cleaning the seal-to-tube with a seal cleaning device or a piece of old 35mm film negative. I usually dip the tool or film strip in power steering stop leak (seal sweller) before trying to work it in between seal lips & fork tube. If the fork is slightly pressurized from prior riding or sun heat it makes inserting  a seal tool or film strip more difficult. Slide the outer (dirt excluder) seal out far enough to get to the actual oil seal under the dirt excluder seal. There is vent screw on the top side of the upper fork tube cap, loosening or removing that will allow pressure release. 

 

You need to loosen that vent screw after the motorcycle is back on it's wheels anyway to allow the pressurized air to escape & equalize. 

 

Over the years I have found that a very large number of seeping/leaking BMW fork seals are just due to gunk build up between the fork tube & seal so cleaning with a little power steering stop leak usually stops the seeping. 

 

The one big problem with just cleaning (if there has been a lot of seepage/leakage) is that you have no way of knowing how much fork oil was lost or is still in the forks.  

 

 

 

 

[9Mary7]

2 hours ago, dirtrider said:

Or you can just  remove the upper tubes  upper nuts then rotate the upper triple tree & work the upper tubes out. (if you remove the upper tubes you will have to find a way to suck the fork oil out).

I did this on my 2011 RT thru the fairings..... should by cake on an R.

[Hadabadachada]

So am I right in assuming the stanchions aren’t actually hard connected? 
 

if I pop a hard enough wheelie I can separate the forks??

[dirtrider]

10 minutes ago, Hadabadachada said:

So am I right in assuming the stanchions aren’t actually hard connected? 
 

if I pop a hard enough wheelie I can separate the forks??

Afternoon Hadabadachada

 

Yes & no!

 

The upper tubes just free float in the lowers (so if all retention is disconnected the upper tubes will just slide out)

 

But they can't come out with a wheelie as the front strut prevents over-travel. 

 

The possible problem with just sliding the upper tubes out (actually sliding them back in through new seals) is the possibility of damaging the new seals with a sharp edges of the vent hole. 

 

You also need to open the upper vent screws when re-installing the tubes to allow the trapped air out of the forks.

 

 

[9Mary7]

9 hours ago, dirtrider said:

the possibility of damaging the new seals with a sharp edges of the vent hole. 

I use cellophane wrapped over the vent holes, around the tube. Lube the seal and it will slide on over the hole with no damage.

[Hadabadachada]

Alright, so I got a little tool as well as some stop leak. 
 

now when I put the tool past the seal, and begin trying to turn it around, I notice the forks move, relatively easily. 
I just held the tool against the fork and spun them together.

 

im just wondering now, is this normal?

 

im thinking maybe I need to tighten something up to keep them in one place.

[dirtrider]

43 minutes ago, Hadabadachada said:

Alright, so I got a little tool as well as some stop leak. 
 

now when I put the tool past the seal, and begin trying to turn it around, I notice the forks move, relatively easily. 
I just held the tool against the fork and spun them together.

 

im just wondering now, is this normal?

 

im thinking maybe I need to tighten something up to keep them in one place.

Afternoon Hadabadachada

 

Yes, normal. The upper joint allows the tube to free-spin. 

 

Did you pry the upper "dirt excluder" seal up to access the main seal? The top seal is not an oil seal, it is simply to keep most of the dirt & gunk out of the lower oil seal. 

[Hadabadachada]

yup, pried that up, wiped everything down best I could, ran the cleaner thing around twice, pumped the suspension, ran the cleaner device again, but dipped in the seal juice you mentioned, pumped the suspension and that’s it.

now a few days later and a hundred plus miles, it looks as tho my stanchions are dry. 
But, keeping an eye on it.

 

thanks again, always great info.