Spark plug and engine oil advice...

Discussion in 'Airheads' started by timesarrow, Apr 16, 2018.

  1. timesarrow

    timesarrow KTM convert...

    Joined:
    Aug 9, 2012
    Oddometer:
    74
    Location:
    Bainsville
    Just became the proud owner of a 1986 R65. I have to replace the plugs and change the oil, among other things. Just looking for a bit of advice as to spark plugs and choice of engine oil? Any suggestions about what works best for these bikes? Currently it has NGK BPR6ES plugs, but one is not firing so looking to replace them and wondering if these are a good choice?
    #1
  2. noman

    noman Long timer

    Joined:
    Jun 4, 2007
    Oddometer:
    2,186
    Location:
    the sticks, southern vt
    if you don't have one, pick up an owners manual. that'll give you oil weight for your temp range, plug type, and plug gap. no idea if you should be using resistor or non-resistor plugs, that will be in the manual too. i assume you swapped the non-firing plug from one cyl to the other to confirm it's a faulty plug. i use NGK plugs, and Mobil One in my '76 corvette, vintage bike projects, and R75/6. they all need the additives for flat tappet engines, other oil manuf offer this.
    #2
    sieg likes this.
  3. sieg

    sieg Wearing out tires......2 at a time, day after day.

    Joined:
    Jul 9, 2008
    Oddometer:
    5,776
    Location:
    Southern Illinois USA
    Yeap RTFM is always good advise.

    But ADVrider needs use another oil thread too.:pep
    #3
  4. WooPig

    WooPig Proudly Patinaed

    Joined:
    Aug 3, 2006
    Oddometer:
    1,718
    Location:
    ArkLaTex
    Congratulations! You’ve chosen a great bike and you’re in the right place to get great advice. (And perhaps a little sarcasm to go with.)
    We like pictures...
    #4
  5. IdahoAirhead

    IdahoAirhead Been here awhile

    Joined:
    Sep 9, 2016
    Oddometer:
    617
    Location:
    S/E Idaho
    That bike should have 5K resistor plug caps, and run non-resistor plugs.
    The stock plug is a Bosch W 7 DC, or a NGK BP7ES.

    What you have is the resistor version of the BP6ES, which is one heat range hotter plug than standard. In combination with 5K resistor plug caps, you would effectively have 10K resistance, which is too high for the electronic ignition and coils.
    If your plug caps have been replaced with non-resistor caps, the resistor plugs would probably work ok, but the recommended combination is 5K caps and non-resistor plugs to be compatible with your electronic ignition.
    #5
    noman and tlub like this.
  6. noman

    noman Long timer

    Joined:
    Jun 4, 2007
    Oddometer:
    2,186
    Location:
    the sticks, southern vt
    :rilla
    #6
  7. mrclubike

    mrclubike Been here awhile

    Joined:
    Aug 11, 2014
    Oddometer:
    498
    Location:
    St Louis MO USA
    #7