Fork-Seal Holiday

Happy Father’s Day to all the dads out there, I’m not one of ’em. Hot days in between the oddly cold days – or maybe because it was a cold day – the right fork-seal on the R1100R up and took a baby-burp, spooging oil all down the fork onto the brake caliper and collecting on the wheel-rim. I caught it when my friend the plumber was over to inspect the irrigation valve-job.
It was purely weird because the bike had not been ridden in two weeks or more, was up on the center-stand with no weight on the front wheel, and no visible cause for such childish behavior besides garage poltergeists.
Meh. I really don’t want to go down to A&S in Roseville – I hate going to Roseville – but I need to see what’s up with this. These are not ordinary or real forks, with springs and damper-rods and valving. These hollow-tube sticks just hold the front wheel together down at one end, and hook-up to the handlebars at the other. All the suspension is done by a car-like shock-absorber on the tele-lever yoke.
So start taking it apart by pulling the right handlebar. Get out the magnetic tray to catch all the bolts, and off with the chrome beauty covers. Take pictures of everything so you can remember how it goes back together…
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Mark the bolts because they’re not all the same length.
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Off comes the handlebar and there’s the fork-top, underneath the rubber cap.
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There’s the bolt that holds it onto the fork-triple-clamp-thing or whatever BMW calls it. It’s nutted down with a air-wrench to some torque…
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There’s other weird doo-dads to record.
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14.3mm is gonna have to be close-enough.
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And my DeWalt impact wrench to break the nut free.
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The sound of a *tink* on concrete alerts me to a hitherto unseen washer that discharged itself.
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Remove the fork-cap doo-dads as you compress the fork and get it aside to slide the top-tube up and out.
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As the guy on the YouTube video says, “I don’t care how %$#@ much oil you lost, you don’t need to go and add any since there’s no use for it besides filling up the tube.” Well OK then. It’s a little brown but it’s high quality synthetic and still very slippery.
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And there’s at least sixteen inches still in the lowers. BMW calls for a whole imperial pint of the stuff and that’s just very…German of them.
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Slide the dust-cover back down and compress tyhe fork against the air-pressure that probably caused the problem in the first place. Spin the little bleeder-screw with the hex-head to relieve the pressure and get it back up into the top-clamp. Nut it back up with the impact wrench when the other doo-dads are aligned.
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20-Newton Meters of torque on these bolts.
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Tighten the clamp to the windshield.
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Replace the chromey beauty-caps and go riding.
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UPDATE: But first clean-up the brake caliper and pads!
UPDATE-UPDATE: Yes it’s a weird fork with no forky-internal bits, just an oil bath.
Da Forks
Sixteen inches of oil is well above the top of the fender, so I probably lost about two inches (?) from the amount on the wheel and brake.
fork level
The Showa shock does all the suspension work, the oil in the fork tubes is for stiction.
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About NotClauswitz

The semi-sprawling adventures of a culturally hegemonic former flat-lander and anti-idiotarian individualist, fleeing the toxic cultural smug emitted by self-satisfied lotus-eating low-land Tesla-driving floppy-hat wearing lizadroid-Leftbat Califorganic eco-tofuistas ~

8 thoughts on “Fork-Seal Holiday

  1. I guess I was confused over the purpose of the job. Sounded at the beginning like you had a blown seal and were replacing it. So you took it all apart just to look at it? Interesting. In the future I would probably dump the oil into a measuring cup and make sure. Since you have it all apart anyway.

    • There’s an oil-bleed screw on the bottom of the fork, so I guess I could still do that. I’ll ride it around and see if it work funny, but I really didn’t want to make a 2-hr round trip down to Roseville on a 100+ day, when it’s a cool 89 up here! 🙂

  2. You might like chasing down the published rumors about the forthcoming 2017 Gold Wing front end.

    It’s rumored to be quite the multilink setup, not quite like the BMW, not quite like the Yamaha Omega suspension, either.

    But yeah, separating the “suspending” from the “steering” as with a conventional fork has every potential for greatness. Guess it’s all in the execution, and rider satisfaction thereafter.

    Certainly though, a bit of reprogramming of the rider’s skills curve comes into play. I’d be curious as to how that affected you with the BMW setup?

    Meanwhile, Honda has the massive single sided swingarm for the ‘Wing, but the pinion still climbs the ring. BMW’s Paralever, doesn’t.

    Patents be damned, just pay the damn royalties. I want to see the best of everything in the heavyweight tourers.

    Jim
    Sunk New Dawn
    Galveston, TX

    • I have not been reading scooter magazines in a long time, so I Googled and got to “Motorcyclist” with a bit and a picture. Oh…kay… Kinda looks like they turned the fork itself into a yoke/wishbone, with some linkages and adjustability. Hmmm. Like they are trying to even more simplify the BMW concept.
      BMW separated suspension chores (compression and damping) from nose-travel and dive, with a shock on the “Telelever” yoke. It’s kinda like half (top or bottom) of a car’s A-arm suspension flipped around. This Honda thing sounds complicated and Honda is not beyond going there, but the Japanese usually try to engineer things to be easier, like the way a single-sided swingarm makes for easier wheel changes.
      I’m not familiar with leading-link designs but I bet hipster moto-journos just like saying that, “leading link!” because it sounds authoritative and gives them journo-cred. 🙂

    • It is sure NOT a dirtbike ten-inches of suspension travel! I for one welcome the lack of juicy wet springs and damping rods with tiny orifices, clogged and fragile and mysteriouis clicky-clicky adjusters on top! But a Schrader bleed-valve would help here a lot with the problem I experienced.
      The KTM’s big fat Marzocchi 50mm fork splits the chores with compression damping on the left side and rebound on the right. The BMW car-like shock absorber is like the KTM’s rear Öhlins, but with only a few inches (if that) of suspension travel.

  3. Wait. What happened to the “replace the leaking seal” step?

    Why wouldn’t you just change the oil if it is apart? How many miles on the bike?

    I don’t know if I would trust a mechanic who says that fork oil doesn’t serve any purpose.
    There’s a spec in your manual as to how far down the oil level “should” be when you are assembling. Oh, and having different amounts on the different sides will lead to different damping on each side.

    • Uh…The bike has only 6,9045 miles on it, and I didn’t have an oil seal/didn’t want to go down to Roseville for one, and don’t have a fork-seal puller. The BMW spec is merely “1-imperial pint,” there’s no oil height or anything.
      The service manual only says:

      • Fill with oil.
      Fill quantity per fixed tube:
      [RS/GS/R/RT] ………………………0.470 l (0.827 Imp. pints)
      Oil grade in telescopic fork:………..BMW telescopic fork oil
      L Note:
      No oil changes required during services: unit is maintenance-free.

      All the damping and rebound and everything is handled by the car-type shock absorber on the yoke. There’s no damping-rods with valves or springs or anything in these forks except oil. There’s a little breather (?) hole on the inner-slider tube for pressure equalization that may have gotten clogged and caused a pressure based/altitude thing. The oil height at over sixteen inches was still way up past the top of the fender (added picture) and there were no nicks in the seal.
      But mainly I had not turned a wrench on this in a long time and wanted to see if I could do it again. 🙂

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