Results 1 to 8 of 8

Thread: Stopped Speedometer - '88 K75S

  1. #1
    Registered User detbmw's Avatar
    Join Date
    Feb 2005
    Location
    Deep East Texas
    Posts
    61

    Stopped Speedometer - '88 K75S

    I have a speedometer problem on my K75S, if you can believe that!

    A year ago the trip meter broke right after my test ride, so I ended up removing the instrument cluster and sending it to Overseas Speedometer in Austin, TX. For the last year since the repair the speedometer has worked reliably. However, a week ago I was washing the bike and while spraying the underside of the windscreen I happen to spray across the face of the instrument cluster. On the next ride the speedo failed to work. In the last 4 gallons of gas (160 miles?) it has worked intermittently and recorded a total of 20.7 miles. When I stopped for gas today I noticed there was sort of a fogging or condensation inside the speedo glass (see pics below). The first picture was at the gas station and the second was at home after the bike had been sitting for a while. I looks like the condensation was disappearing after a while.

    So it looks to me that I managed to get water inside the speedometer and it will not work until I get it out.

    Am I correct?

    Where do I go from here?

    Rich
    (speeding in Texas)

    photo11_zpsd9ea126b.jpg

    photo13_zpsb8b03143.jpg
    Rich
    Night Black 2000 R1100RT
    Marakesh Red 1988 K75S "The S is, by far, the finest-handling BMW we have ever ridden." Motorcyclist, November 1986

  2. #2
    Debbie's Servant Lee's Avatar
    Join Date
    May 2003
    Location
    SW Iowa
    Posts
    1,516
    On our K75's the dash would fog, then clear up after riding in the rain or washing the bikes and it never affected the speedometer. I can see where over time the connections could corrode and cause problems.
    Did your speedometer and odometer both quit or just the odometer?
    Lee 2011 K1300S
    MOA # 30878
    Past BMW Bikes, 2003 K1200RS, 1991 K75S, 1987 K75T, 1984 R100RT

  3. #3
    Registered User detbmw's Avatar
    Join Date
    Feb 2005
    Location
    Deep East Texas
    Posts
    61
    Quote Originally Posted by Lee View Post
    On our K75's the dash would fog, then clear up after riding in the rain or washing the bikes and it never affected the speedometer. I can see where over time the connections could corrode and cause problems.
    Did your speedometer and odometer both quit or just the odometer?
    Both have failed. When one works, the other works too.
    Rich
    Night Black 2000 R1100RT
    Marakesh Red 1988 K75S "The S is, by far, the finest-handling BMW we have ever ridden." Motorcyclist, November 1986

  4. #4
    Benchwrenching PGlaves's Avatar
    Join Date
    Oct 2003
    Location
    "Big Bend" TX
    Posts
    8,729
    Later classic K speedometers had some vents covered with what was reputed to be Gortex. Thus if moisture did get in it could evaporate away through the membrane but for the most part water couldn't get in. I forget when this started but I suspect it was later than your bike.

    I would park the bike in a good warm place, or even out in the Sun to try to evaporate the moisture out of the housing. If that fails to work because it is semi-sealed, then you will have to take it off and open the case to let the moisture evaporate away. While you are there, some circuit board cleaner and compressed air blown on the circuit board and other connectors will help.
    Last edited by PGlaves; 11-29-2013 at 03:54 PM.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  5. #5
    A bozo on the bus deilenberger's Avatar
    Join Date
    Mar 2003
    Location
    Spring Lake NJ, USA
    Posts
    7,736
    One thing that worked with both my K bikes - a wrap of black vinyl electrical tape around the joint between the front bezel and the case. The seal there is a light foam-rubber O ring - of large diameter. With age it is going to seal less well.. Get the cluster dried out, then put the electrical tape around the joint and chances are your fogging will not reappear.
    Don Eilenberger http://www.eilenberger.net
    Spring Lk Heights NJ NJ Shore BMW Riders New Sweden BMW Riders
    '07 R1200R (current ride) and some bimmers.. and a Porsche

  6. #6
    3 Red Bricks
    Join Date
    Jan 2007
    Location
    Pleasanton, Ca.
    Posts
    3,401
    To make SURE that the problem is in the cluster or it's connection: Does the self canceling turn indicators still cancel while the speedometer is not working? If not, the problem could be the sensor or it's connector.



    LONG MAY YOUR BRICK FLY!

    Ride Safe, Ride Far, Ride Often

    Lee Fulton Forum Moderator
    3 Marakesh Red K75Ss
    Mine, Hers, Spare

  7. #7
    Registered User detbmw's Avatar
    Join Date
    Feb 2005
    Location
    Deep East Texas
    Posts
    61
    I finally took the bike on a two-hour ride. After about thirty minutes it had fogged up again and suddenly the speedometer & odometer began working. The next time I rode the bike, they both worked again. I guess the water evaporated off of whatever it was clinging to!

    Rich
    (still speeding in Texas, but now I know by how much)
    Rich
    Night Black 2000 R1100RT
    Marakesh Red 1988 K75S "The S is, by far, the finest-handling BMW we have ever ridden." Motorcyclist, November 1986

  8. #8
    UJ tio jaimito's Avatar
    Join Date
    Dec 2012
    Location
    Near Highwood, IL
    Posts
    32

    Intermittent function on speedometer.

    I have had fogging on both my 1985 K100rs' and to a lesser degree my 1987 K75s' speedometers. The 1987 dried out on it's own, while I removed, disassembled and inspected the non-vented KRS unit. I cleaned and wiped down the interior. I found that the bezel gasket was cracked and hard. I bought a new one. Reinstalled it. And it works better with better fog resistance. I cover the speedo when I wash it or when I am riding in the rain, now. A clear bag worked nicely.
    A typical temporary cure for both of the stopped function was to tap on the speedo.

    Jim

Posting Permissions

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