FOAK: Using low octane and leaded fuel

Discussion in 'UK Motorcycles' started by YTC#1, Feb 17, 2011.

  1. YTC#1

    YTC#1 Guest

    A techie Q

    Down to using 84 octane in the bikes at the moment, and I suspect that it
    may be unleaded ( a notice on a pump in Peru said "low lead") and Bolivia
    is well... Bolivia.

    Bikes are running a touch rough, but so are we at over 3800 metres :)

    Should be in Chile tomorrow so will be (hopefully) back on higher octane

    What does the FOAK say ?
    YTC#1, Feb 17, 2011
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  2. YTC#1

    Higgins Guest

    I have a vague recollection[1] that the octane is lower because of the
    low oxygen density at altitude, otherwise it would be running too rich,
    but wibble flip, etc.

    [1]I might have heard it on NPR Car Talk.
    Higgins, Feb 17, 2011
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  3. YTC#1

    Adrian Guest

    Whose measurement? Given the location, wouldn't surprise me if it was US
    RON+MON/2 - which comes out a lot lower than our RON. Their cooking is
    87, which is about equivalent to the 91 available some places on the
    continent. Their 89 is about our 95.

    So that juice might be shite, but it's probably not as shite as you're
    thinking it is.
    Adrian, Feb 17, 2011
  4. YTC#1

    YTC#1 Guest

    **** nose
    I know all about the ron,mon,pon crap

    But 84 is *low*
    And the lead ?
    YTC#1, Feb 17, 2011
  5. YTC#1

    YTC#1 Guest

    I've heard rumours of such, but with the bike being FI, does the on board
    ECU not decide it needs to alter stuff ?
    YTC#1, Feb 17, 2011
  6. YTC#1

    Adrian Guest

    I vaguely remember lead in petrol.

    There's no cat on the bike, is there?
    Adrian, Feb 17, 2011
  7. YTC#1

    Adrian Guest

    Does it have a knock sensor?
    Adrian, Feb 17, 2011
  8. YTC#1

    YTC#1 Guest

    Dunno, but it moan like **** when I drop it ! :)
    YTC#1, Feb 17, 2011
  9. YTC#1

    Adrian Guest

    Easy solution to that one...
    Adrian, Feb 17, 2011
  10. You are going to *love* Chile.

    And Patricio & family will be fantastic hosts. Tell the bugger when you
    see him, that I've saved a bottle of Longrow cask strength (courtesy of
    Colin Irvine) for him and will bring it out in July.
    The Older Gentleman, Feb 17, 2011
  11. YTC#1

    YTC#1 Guest

    No, no CAT
    YTC#1, Feb 17, 2011
  12. YTC#1

    YTC#1 Guest

    Yes, and I think I can get a new side stand cut out switch for Jean's
    bike there, she had an argument with a railway line while detouring
    around a classic Bolivian road block.
    Will do

    You sorted out a new piece of land yet then ?
    YTC#1, Feb 17, 2011
  13. YTC#1

    Pip Luscher Guest

    Or an absolute pressure sensor, or an air mass flow meter?

    TBH, it's likely to have the former but not the latter; bike (and many
    car) ECUs tend to work on indirect airflow measurement.
    Pip Luscher, Feb 17, 2011
  14. No, but we will.
    The Older Gentleman, Feb 17, 2011
  15. YTC#1

    Mark Olson Guest

    If it's (RON+MON)/2 that's fine at the altitude you said you were
    What about it? If your bike doesn't have a cat it won't matter
    if there's lead in it or not.
    Mark Olson, Feb 17, 2011
  16. YTC#1

    YTC#1 Guest

    Oh, and I am starting to understand why you like SA. So far I could
    settle in Peru or Ecuador.
    YTC#1, Feb 17, 2011
  17. YTC#1

    YTC#1 Guest

    Can some one explain the low octane/altitude thing please ?
    I've heard about it, but never understood it .

    That is what I wanted to hear.
    YTC#1, Feb 17, 2011
  18. YTC#1

    ogden Guest

    Can't you just permanently bypass it? It was the first mod I had to make
    to the KTM after I bought it.
    ogden, Feb 17, 2011
  19. YTC#1

    YTC#1 Guest

    That is one plan, I have the wiring diagram now, just need to work out
    where it all goes (the is a lot of mud till stuck underneath), oh, and
    find somewhere with nice electrical bits... probably in Chile.
    YTC#1, Feb 17, 2011
  20. YTC#1

    Eiron Guest

    Higher altitude means lower cylinder pressures so lower octane fuel is
    And the oil companies probably know what they are doing so sell the
    right fuel
    for modern cars, if not old motorcycles.

    Reduced power goes without saying but if you have carbs you are
    running rich, which might explain the rough engine.
    Eiron, Feb 17, 2011
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