Results 1 to 6 of 6

Thread: Fork Question...Missing Part?

  1. #1
    Registered User
    Join Date
    Apr 2012
    Location
    Gilbert, AZ
    Posts
    280

    Fork Question...Missing Part?

    Bike is 83 R100RS, 47k miles. I removed the fork sliders to replace the leaking seals. The oil (what there was of it) was really filthy and lots of crud in the bottom of the sliders. I took the forks apart and cleaned everything and am now putting it back together. I'm a bit confused, tho, because I have a spring that does not show in the fiche and I don't have a part that is in the fiche (31422301015 - Support for damper rod). I'm told there should be a bumper in there but that it often disintegrates over time. Is that what the missing part is...perhaps that was the source of the crud? Or does that spring replace the bumper? Or ???

    Here are a couple pictures showing the spring:

    http://i1125.photobucket.com/albums/...x/IMG_1449.jpg

    http://i1125.photobucket.com/albums/...x/IMG_1450.jpg

    Of course, the bolt in the end is the one that holds the slider on. And the washer would be inside the slider. I just screwed it together for illustrative purposes.

    Thanks... Mark

    [Also posted to Airheads mailing list]
    1983 R100RS (Sold)
    2004 R1150RT
    BMW MOA 181289
    ABC 13558

  2. #2
    Registered User kwb210's Avatar
    Join Date
    Jul 2009
    Location
    Washington, the state
    Posts
    276

    bumpers at the bottom

    The bumpers usually sit at the bottom of shock components. Take a look at Max BMW parts fiche for a reference, usually right on and helpful. Yes, the bumpers decompose over time and turn to liquid goo. They must be replaced. The spring thing I am not sure of as my newest bike is a 1977. I almost always replace the bottom bumpers when I get a new bike, then, just the oil for the first couple of years. But I alwyays inspect them for condition. SOrry can't help on balance of post.
    Regards,
    Kurt
    1977 R100/7 1971.1972.1972.1973 R75/5
    1974 R90/6 multiple boxes
    Airhead Revival
    "Objects in the mirror appear to be losing" unk

  3. #3
    Registered User donbmw's Avatar
    Join Date
    Feb 2004
    Location
    Monroe La.
    Posts
    450
    Those springs maybe the after market anti dive springs that were around at that time.
    1975 R90/6, 1980 and 1982 R65, !959 TR3A Triumph Car

  4. #4
    edbmw
    Join Date
    May 2006
    Posts
    25
    Probably San Jose or Luftmeister springs. I've used em in the past and they seemed to work for me. Course, a spring will only do so much.

    http://www.bmwmoa.org/forum/showthre...i-dive-Springs

    Can't believe this popped up in a google search.

    http://www.ebay.com/itm/BMW-1981-198...-/380583405445
    1978 R100 Jacked up for off road fun and urban adventures.

  5. #5
    Registered User
    Join Date
    Apr 2012
    Location
    Gilbert, AZ
    Posts
    280
    Thanks for the replies, guys. The consensus seems to be that the springs are indeed an aftermarket anti-dive mod and that I'm missing the 'Support for damper pipe', #17 in the fiche. Max's parts guy (Drew) says they have to be ordered from Germany. Looks like it'll be a while before I get it back on the road. And the weather is really nice here now. Oh well...the joys of old motorcycles...

    I'm tempted to buy that kit off eBay, at least in the meantime...
    1983 R100RS (Sold)
    2004 R1150RT
    BMW MOA 181289
    ABC 13558

  6. #6
    Registered User bmweuro's Avatar
    Join Date
    Oct 2009
    Location
    Northern Cal
    Posts
    255
    The springs over the damping rods are old Luftmiester anti dive springs. After 1980 BMW did not put a bumper in the bottom of the fork. By new factory BMW fork springs if your bike has over 50k miles. Do not buy the Progressive brand springs. While your at it throw away the anti dive springs. With the right fork oil you will be very happy how the bike rides.
    www.boxermetal.com
    www.facebook.com/boxermetal
    VBMWMO #7770, BMW MOA #48694, ABC #600
    Hi my name is Chris and I am a slash-five-o-holic.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •