Results 1 to 6 of 6

Thread: K100 engine/valve cover.

  1. #1
    Registered User
    Join Date
    Nov 2005
    Posts
    73

    K100 engine/valve cover.

    Hi All,

    I'm looking to check the valve clearnace and have sources the inner and outer gaskets and 8 rubber bushings for the head bolts. But there are the outer 3 bolts with rubber bushings (circled in red) that I can't find part numbers to. Does anyone know where I can get them?
    Attached Images Attached Images
    Chuck
    Current: 1985 K100RS
    Previous: 2002 R1150GS, 1990 Suzuki VX800, 1993 Honda CBR600F2, 1988 Honda CBRF, 1978 Honda Passport

  2. #2
    3 Red Bricks
    Join Date
    Jan 2007
    Location
    Pleasanton, Ca.
    Posts
    3,140
    They are the same as the other ones. And you missed two more (the ones in front of and behind the BMW spark plug cover). You need 12 bushings for a K100. 10 for a K75.


    LONG MAY YOUR BRICK FLY!

    Ride Safe, Ride Far, Ride Often

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

  3. #3
    Registered User
    Join Date
    Nov 2005
    Posts
    73
    Thanks Lee.


    I ordered and got 8. Can I re-use 4 of the old ones if they look good?
    Chuck
    Current: 1985 K100RS
    Previous: 2002 R1150GS, 1990 Suzuki VX800, 1993 Honda CBR600F2, 1988 Honda CBRF, 1978 Honda Passport

  4. #4
    Registered User
    Join Date
    Apr 2012
    Location
    Los Angeles, CA
    Posts
    274
    Quote Originally Posted by cy7878 View Post
    Thanks Lee.


    I ordered and got 8. Can I re-use 4 of the old ones if they look good?
    You risk leaks by doing that, as it's the pressure of the compressed rubber bushings that holds the cover firmly against its gasket. The screws have shoulders that butt up against the head surface, meaning that tightening the screw beyond its very minimal torque spec doesn't actually increase the pressure of the screw head against the cover. (And this is important - if you tighten it beyond the spec, you very quickly run the risk of breaking the screw off in your head.)

    The cover, gasket, and head may be held together mostly by age and gunk at this point, so once you open it up you're liable to have weeping out the edges if you don't use new rubber bushings all around.

    If you don't want to wait for the additional four to arrive before doing the work, you could certainly put four old ones back and replace them when they arrive, but I'd say it's a near certainty you'll want to replace them.

    Edit: Four out of twelve is 33%. So, assuming that your old ones are by now dry and compressed to the size of the space they're in and exerting approximately zero pressure on the valve cover, re-using four of them means your cover will be held against its gasket with only about two-thirds of the design pressure.

  5. #5
    Debbie's Servant Lee's Avatar
    Join Date
    May 2003
    Location
    SW Iowa
    Posts
    1,300
    Quote Originally Posted by cy7878 View Post


    I ordered and got 8. Can I re-use 4 of the old ones if they look good?
    Since your bike has enough age on it I would replace all of them. After that you'll be good for many more years.
    In approx. 440,000 miles on our brick engine bikes I only replace the valve cover gaskets and little half moon things once, and never replaced any of the bushings.
    The K75Ss were around 10 years old when I replaced the gaskets.
    Lee 2011 K1300S
    MOA # 30878
    Past BMW Bikes, 2003 K1200RS, 1991 K75S, 1987 K75T, 1984 R100RT

  6. #6
    Registered User
    Join Date
    Nov 2005
    Posts
    73
    Thanks all for the reply. I will order 4 more.
    Chuck
    Current: 1985 K100RS
    Previous: 2002 R1150GS, 1990 Suzuki VX800, 1993 Honda CBR600F2, 1988 Honda CBRF, 1978 Honda Passport

Posting Permissions

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