Fuel octane

Discussion in 'Engine, Fuel and Exhaust' started by HarleyHarry, Jun 16, 2007.

  1. HarleyHarry

    HarleyHarry Banned

    Hi All

    After having had 2 Harleys that I bought 2nd hand I have now bought a new Ultra.
    As I would like to keep her in top condition for as long as possible I would like to ask you all what sort of fuel to go for.
    I live in England and the choises here are 95 and 98/99 octane.(the high octane goes well over $2.03/ltr)
    Bikes destined for the UK, I'm sure, are modified to take this high octane as I know in the US it's much lower (isn't the max 92, sold by Shell?) but does it make sense to go for the highest rating when it comes to being better for the bike.
    I'm not looking for more performance, I bought the bike to relax . If I want to get somewhere fast I take a train/plane. (the high octane goes well over $2.00/ltr)
    Any advise would much appreciated.
  2. leapfreak

    leapfreak Active Member

    HarleyHarry - Hobbit is correct with what he told you but let me add one further comment. H-D makes an Fuel Additive that I have used in my ride. Sells for $5.95USD and treats 8 tanksful (if you have a 5 gal tank). I use regular unleaded gas (89 octane - much lower price), add one measured amount of the booster and it runs as if I had put the high price stuff in it. No pinging of the pistons at all. It's called "Genuine Fuel Additive" and the H-D part number is 99893-91A.
  3. waterdog

    waterdog Active Member

    Good info Leapfreak. I've never heard of that additive before and might try it.
  4. glider

    glider Veteran Member

    I find that a drop from Sunoco 93 to 91 actually makes it run better. The higher octane will also run a bit hotter too.