K75 won't Start

Discussion in 'Old's Cool' started by NickW1, Feb 8, 2011.

  1. Dan Cãta

    Dan Cãta Long timer

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    Not meaning to hijack the owner's topic, I have a friend that has some starting issues with his k75, '86. He reports that the spark plugs fire when they should, but the gas squirts are all at the same time.

    My experience with k bikes is limited to the 1200 series. Does anyone have any idea on where to start troubleshooting?

    Dan.
    #21
  2. LonerDave

    LonerDave Been here awhile

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    No experience, but have heard that the threes are much smoother than the fours. Suspect it has something to do with 3 going into 360 degrees (120 degrees) so much better than does 4 at 90 degrees. But like I said, never ridden either one.
    #22
  3. ericrat

    ericrat Long timer

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    I don't know for certain, but my experience tells me that would be correct. The k75 fuel injection is probably a "batch" fire system where the injectors all fire at the same time. This would be very common on that era injection and it works fine.

    The K75 wires have a gap built into them. You can't resistance test them.

    Eric
    #23
  4. damurph

    damurph Cold Adventurer

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    K75 was a smoother motor because they had to install a balancer that the four cylind r did not require.
    3 cylinder/four stroke.
    I have a few KMs with one under my ass.
    #24
  5. H96669

    H96669 A proud pragmatist.

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    Wondering about that "fire as they should"??? That's a wasted spark system, they should all fire at once.:ear
    #25
  6. Dolly Sod

    Dolly Sod Red Clay Halo

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    Wasted spark doesn't mean the plugs all fire at once. It means they fire every stroke. Once on compression and once on exhaust. The spark still has to be properly timed.
    #26