Yet Another K100 Rebuild

Discussion in 'Some Assembly Required' started by hitmanh, Aug 17, 2019.

  1. hitmanh

    hitmanh Been here awhile Supporter

    Joined:
    Dec 12, 2008
    Oddometer:
    287
    Location:
    Cambridge, UK
    Hi all,

    So I've had a 1991 K100 with 81k miles on the clock sitting in my garage looking sad and lonely for a few years. It was originally an LT when I bought it, I eventually stripped the fairing and bags from it and sold them off. Rode it for a year or so then the ABS died and it ended up being SORNed (declared not in use and thus avoided annual road tax).

    Originally looked like this:

    BMWK100.jpg
    Then dump the fairing soon after

    IMG_20190817_152020.jpg
    So current plan is to:

    Phase 1:
    Strip ABS system and replace all hoses with new
    Fix an oil leak, I think it's engine output seal
    Replace handle bars and console with something less 80s
    Service engine, replace all fluids, spark plugs and , valve check
    Service coolant pump
    Clean up and paint rusty metal work (mainly crash bars, and stands)
    New front light and indicators
    Get MOTed (annual inspection) and taxed and back on the road

    So, first job is strip of the console and lights

    ha, even found the original topol kit. IMG_20190817_152916.jpg

    IMG_20190817_152029.jpg
    And temp fitted a GS bar I had spare.
    IMG_20190817_164625.jpg IMG_20190817_164636.jpg

    Please note this will be a slow build thread as I can only work weekends on this
    #1
    flinders_72 likes this.
  2. hitmanh

    hitmanh Been here awhile Supporter

    Joined:
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    Phase 2, aka pimp my ride
    Go single seat
    Make the rear end tidier
    Possibly fork/triple upgrade
    #2
  3. hitmanh

    hitmanh Been here awhile Supporter

    Joined:
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    Cleaned and lubed chain on the F800 today, sprockets are worn so ordered new chain/sprocket kit.

    On the K100, finished stripping the bars/controls and other minor bits and pieces.

    Looking very crusty down low.

    IMG_20190818_143534.jpg

    Have new water pump cover and bolts ready to go, once i've given the engine a good clean.
    #3
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  4. hitmanh

    hitmanh Been here awhile Supporter

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    #4
    Jim K in PA and flinders_72 like this.
  5. mjs3800

    mjs3800 Adventurer Supporter

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    That White one is sweet. Interested to see where you go with this.
    #5
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  6. hitmanh

    hitmanh Been here awhile Supporter

    Joined:
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    Some inspiration:

    31_01_2017_NCT_Motorcycles_BMW_K100_Brat_Tracker_Austria_Pipeburn_Custom_Motorcycle_06.jpg
    BMW-K100-Scrambler-1.jpg
    BMW-K100-Tracker-9.jpg
    DSC_9392-Edit-1.jpg
    titan-bmw-k100-xavier-01.jpg
    #6
  7. JimVonBaden

    JimVonBaden "Cool" Aid! Supporter

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    #7
  8. hitmanh

    hitmanh Been here awhile Supporter

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    I think it's mainly about the look rather than actually getting muddy. I do have the wheels from one of these to play with.

    [​IMG]
    #8
  9. JimVonBaden

    JimVonBaden "Cool" Aid! Supporter

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    Yeah, just the knobbies on cast rims and a Cafe Racer looking bike, makes no sense to me. Plus you lose smoothness and grip.
    #9
    hitmanh likes this.
  10. r60man

    r60man Long timer

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    The knobbies are all show no go, especially on a wet road. But of course most customs are garage queens that never actually see the rain. That said getting good road rubber for the original wheels for the K bikes is getting harder and harder to do.
    #10
  11. flinders_72

    flinders_72 Long timer

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    Sweet was what came to mind when I saw it. Best looking K I've seen.
    #11
  12. hitmanh

    hitmanh Been here awhile Supporter

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    Exactly, this has to be a practical daily rider and as I'm UK based that means getting wet on a semi-regular basis. Defo not going for knobbies as I'll never be taking this off road and I want all the grip I can get in all weather conditions.
    #12
  13. hitmanh

    hitmanh Been here awhile Supporter

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    So, I was planning for a full afternoon of work on the bike today, but the temp has shot up from a pleasent 75 to a rather less pleasent 90, so I had to give up after an hour becuase my pale British arse cannot cope in this heat.

    Stripped both pegs sub frames/panel things including half an ass ton of rear brake/abs unit and cables.

    IMG_20190824_143331[1].jpg

    Wanted to get the exhaust off, but unsurprisingly everything is rusty and filthy, so gave all bolts a scrub with a wire brush and soak in penetrating oil and will have a go in a few days (and have the dremel on standby).

    Otherwise pulled off various bits of wiring, removed a ton of cable ties, removed the rear plastics and getting close to being able remove frame and wiring harness (just need to label up important cable plugs for later).
    #13
  14. hitmanh

    hitmanh Been here awhile Supporter

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    The wired wheels do look good, I'm surprised they're not used more often (and you get better tire options versus the old wheels).

    10257387_705673219496564_2344845477552795487_o.jpg
    OFVRO.jpg
    #14
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  15. hitmanh

    hitmanh Been here awhile Supporter

    Joined:
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    Oddometer:
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    bit_rusty.jpg

    So, abck in the garage for a few hours today. Usual arse end rusty frame

    IMG_20190907_132723.jpg
    Potential donor wheel.

    Swing arm/bevel box now removed. Some wear on the bevel box input shaft

    IMG_20190907_134305.jpg
    And a filthy rear end

    IMG_20190907_135133.jpg
    Auxilary motor?

    IMG_20190907_135314.jpg
    Currently awaiting delivery of something to support the engine before I pull the gear box and frame.

    Cheers

    Matt
    #15
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  16. hitmanh

    hitmanh Been here awhile Supporter

    Joined:
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    Oddometer:
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    Right some minor progress this week. I'ved dropped the fluids, and everything looks fine, engine oil and coolant all looked good and no signs of any cross contamination, yay. Gearbox/final drive oil was perfect with no worrying items stuck to the magnets on the drain plugs.

    Removed forks and crash bars

    IMG_20190914_123254.jpg

    I have a set of progressive springs to go in the forks, so complete strip and service of the forks will happen. The triple trees are ugly, but otherwise in fine condtions, so they'll get a good clean and maybe a paint job. Undecided as yet.

    IMG_20190914_123330.jpg
    And engine support is in and cranked up.

    Front brakes calipres are actually in good contition despite all the corrsion on the pipe work. I have service kits for these, so they will br stripped down, cleaned and fresh hoses fitted at some point.

    IMG_20190914_123451.jpg

    My intention is to use an M-unit Basic to control lights, horn, indicators, etc, and doing away with many of the existing relays and the wiring box.Most of the wiring is going to be stripped out, along with ABS wiring and hoses, pretty much only the engine related wiring will remain original, so I need to labled up those connectors then I'm good to pull the frame and wiring harness.

    More info on the M-unbit here: https://motogadget.com/shop/en/m-unit-basic.html

    I'm away for the next week so it'll be a couple of weeks for the next update.

    In the mean time I can recommend the following viewing:




    And edit a million times, despite working in IT for over twenty years, my typing is utter bollcoks.
    #16