Ohlins fork seals

[Chuck]

Then, you can remove the spring.. you can grab it with your new coat hanger "special tool"

2017-02-12_11-15-33 by Charles Stottlemyer, on Flickr

When you remove the fork from the soft jaws, remember the fork is now ready to come apart. Don't let it do that..

 

Now, you can empty the oil, keeping your finger over part of the piston shaft where the needle valve and spring will eventually find their way out. You can see them here. When they come out, some more oil will come, so be ready to catch it in your "graduated cylinder."

2017-02-12_11-16-01 by Charles Stottlemyer, on Flickr

Here's what they look like..

2017-02-12_11-16-21 by Charles Stottlemyer, on Flickr

Looks like it'll take a half liter.. or a little more if you include all if it that I didn't get into the measuring cup. Some more oil will come out when you remove the inner tube from the outer. Do that now.

2017-02-12_11-17-01 by Charles Stottlemyer, on Flickr

Put the outer tube back in the soft jaws..

Remove the dust cap. A small screwdriver tapped in around the edge will bring it up a little, then a larger screwdriver will lever it up. Be gentle.

2017-02-12_11-17-22 by Charles Stottlemyer, on Flickr

Once that is out, you'll see a snap ring. Fortunately, it's not the "Snap Ring From Hell" that I found on the Aero engine conversion.

2017-02-12_11-17-45 by Charles Stottlemyer, on Flickr

It's round, so I just used a small scriber to work in behind it and lever it out. About anything sharp should do it.

2017-02-12_11-18-01 by Charles Stottlemyer, on Flickr

[Chuck]

This is a seal hook. It's pretty obvious how it works..

2017-02-12_11-18-32 by Charles Stottlemyer, on Flickr

You can see where I've pulled the seal a little of the way up on one side. Going around and levering it against the fork leg will pull it right out. Try not to beat up the end of the fork tube like the last guy that was here did. I know who it was, and I'm not surprised, honestly.

2017-02-12_11-18-48 by Charles Stottlemyer, on Flickr

There is a simple stamped flat washer under the seal. The smooth side faces the seal, naturally.

2017-02-12_11-19-04 by Charles Stottlemyer, on Flickr

Clean everything up in the solvent tank, and we're ready to reassemble with the new seals.

But first. We need a seal driver. If you plan to do this, and don't have a lathe, just buy the proper tool. That way you can put the new seal on the inner tube and drive it in to the outer. It'll be doweled together.

I decided to do it the quick and dirty way. Went into my "In my lifetime" area, and found some pvc pipe.

2017-02-12_11-19-23 by Charles Stottlemyer, on Flickr

Sawed it off, cleaned it up, chucked it up, and made a seal driver. 1.830" ID and 2.155" OD.

2017-02-12_11-19-39 by Charles Stottlemyer, on Flickr

Added a little chamfer

2017-02-12_11-19-52 by Charles Stottlemyer, on Flickr

So it won't mark the seal lip.

Now, we're ready to install the seal. Don't forget that flat washer that goes underneath it.

Ohlin's sez

"9
Remove the outer tube, clean the seals
and check for damage, if the seals are
damaged remove and replace. If the
seals are OK, then apply Ohlins grease"

 

To me it sounds ok to just install the seal and assemble the forks. After all, you have to take the forks apart to service them.. why would you have to use the 2 piece seal driver to install the seals in assembly?

I'm betting a hundred dollars (seals and oil) that you don't.

[Chuck]

Whew! It took longer to tell about it than to do it. I suppose that is why I couldn't find anything like this on the net. A pro doesn't have time to waste documenting this stuff. It's play for me.

I hope it helps the next guy (or girl) that finds this with a search.

[BigBlock]

Great write up and pictures Chuck.   This should go into the How To section.

[leroysch]

Appreciate you taking the time and photo-documenting. Thanks!

[czakky]

Awesome! Thanks Chuck!

[Chuck]

My pleasure. If I find anything notable when I put them together, I'll post it. It looks to be straightforward.

[Chuck]

Well, in the spirit of "We're here, might as well.. that we all know so well :grin:" I thought I'd go ahead and document the reassembly. Lube up the leg and seal well, sit it squarely on the fork leg.. you *did* remember the flat washer that goes underneath it, right? ..and drive it home. It won't take much.

2017-02-13_11-26-43 by Charles Stottlemyer, on Flickr

It'll bottom out on the washer, and give room for the little snap ring. Install it with your fingers.

Lube the dust cover and slide it down on the inner tube.

2017-02-13_11-27-04 by Charles Stottlemyer, on Flickr

Because the new dust cover and seal will be going beyond their normal travel, make sure all the bug guts, rock dings, etc. are cleaned up.

2017-02-13_11-29-28 by Charles Stottlemyer, on Flickr

Unfortunately, one of them wasn't bug guts. I looked at it with a 10x power glass, and it was a raised chip of metal or coating. Donned my old mold maker's hat, and carefully stoned it off with a hard fine stone.

2017-02-13_11-29-52 by Charles Stottlemyer, on Flickr

Now, we're ready to continue.

[Chuck]

Lube the seal some more and the end of the inner tube, making sure there isn't a burr or anything on it. Carefully slide it in, and when it gets into the bushing, you have it made.

2017-02-13_11-27-25 by Charles Stottlemyer, on Flickr

Pull the dust cover (Olhlins calls it a scraper) down, and push it home with your fingers.

2017-02-13_11-27-44 by Charles Stottlemyer, on Flickr

Loosen the soft jaws, turn the leg over and push the outer tube all the way down. Back into the soft jaws.

Now is a good time send the spring, then the needle on their way to the bottom of the piston shaft. You can help them get there with the spacer tube. Once it's there, you'll feel the needle valve working with your finger on the end of the spacer tubing.

 2017-02-13_11-28-18 by Charles Stottlemyer, on Flickr

Drop the spring in after noting the part number etched on the top coil for posterity.

Then, the "gizmo" on top. It doesn't matter which way it goes, but it's easy to see this side went against the spring.

2017-02-13_11-28-40 by Charles Stottlemyer, on Flickr

[Chuck]

Put *some* oil in. We're not trying to fill it yet.. maybe 400cc or so. Reach in, grab the rod and pull it up. You'll hear "That Great sucking sound.." of the piston filling. Exercise it several times. When all is full, there will be no more gurgling, etc. When you let go, it'll slowly go down, depending on your setting on the bottom of the fork. We haven't changed anything, so there will be no need of looking up settings, etc.

Nice..smooth.. no gurgling. Gots it?

2017-02-13_11-29-04 by Charles Stottlemyer, on Flickr

Top up the fluid to an air gap of 105mm, according to "the book." This is with the fork fully collapsed, spring in, measured from the top of the fluid to the top of the outer tube. Because we may or may not have the same spring installed, your volume may be vary.

Pull the tube up, and run the jam nut all the way on.

2017-02-13_11-30-14 by Charles Stottlemyer, on Flickr

Almost done. Hmmm, in my excitement or something, I forgot to take a couple of pictures. At any rate, you've seen how slowly the piston shaft drops once you let it go? There's time to let it go, install the spring spacer tube, and grab it again. Then, if you hold the spacer down against spring tension, the top is easily spun on. Run it down until it bottoms, then hold the jam nut with a 17mm wrench, and tighten the blue nut.

Loosen the soft jaws and pull the outer tube up a few inches. This will let the top assembly settle on the outer tube where you can tighten it with your pin spanner.

Run the preload nut in the number of turns you originally counted, and you are done.

2017-02-13_11-30-32 by Charles Stottlemyer, on Flickr

No suspension settings have been changed.. all you did was put in new seals and fresh oil. It's ready to go back in the bike. Now, *you* are an Ohlins suspension specialist..

Exercising the fork several times just left a very little residual oil. I *assume* it's just from the lube on the seals and (especially) scraper.

2017-02-13_11-30-51 by Charles Stottlemyer, on Flickr

Now for the bad news.. as I expected when I measured the used oil, it took a little over a half liter.

2017-02-13_11-31-23 by Charles Stottlemyer, on Flickr

I first thought, "Oh, I could top it up with some bel ray fork oil that I have up in the Guzzi Garage ™.. or top it up with just a little (ahem) used oil."

No.

I'll make the 50 mile round trip to the Duck dealer, and see if they'll sell me something smaller than a $30 liter.

That's it. Hope you got as much info from this as I did.

[Scud]

Fabulous Chuck. 

 

FWIW - I bought 2 liters of that oil. Then when I decided to have a shop do the work I gave them all my supplies. They returned my 2nd liter with about 900ml remaining. That's why I had a bottle handy to take a picture for you earlier.

[Chuck]

Fabulous Chuck. 

 

FWIW - I bought 2 liters of that oil. Then when I decided to have a shop do the work I gave them all my supplies. They returned my 2nd liter with about 900ml remaining. That's why I had a bottle handy to take a picture for you earlier.

Thanks, Scud. Yeah.. that's about what I need.. an extra maybe 200 ml to be safe. Ran that 1:45  round trip to the Duck dealer, hoping for the best. Didn't realize they were closed on Mondays.     Winter hours.. no doubt, you don't have to deal with that. Oh, well. Maybe I can *ride* there tomorrow. It's forecast to be 45 degrees and not raining. Life is good, anyway.

[Scud]

Most motorcycle dealers are closed Sunday and Monday here. Tomorrow is Valentines Day. Go get your sweetie something special at the Ducati dealer. Oh... and maybe get something for you wife too.

[JRD]

Awesome write up Chuck, and thank you so much for taking the time to photograph the procedure step by step.  I am a "visual learner" and it helps so much to see an actual photograph of something as it is being explained.  

 

Im guessing the procedure will pretty much be the same for the Showa forks?

 

 

 

Jerry

[docc]

Good question about the procedure applying to *other* forks?

 

(The *other* V11 forks are a couple different types of Marzocchi?)