Fuel

Discussion in 'Touring Models' started by Subby, Jul 14, 2010.

  1. Subby

    Subby Active Member

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    I recently completed a 4000 mile trip from Canada, through the US southwest and home. There were 4 Ultra classics in our group representing model years from 2007 to 2009. We all experienced a lot of engine rattle under load when using the US 91 octane gas with 10% ethanol. Even adding octane boost did not eliminate the rattle although it did improve things a bit. Once we got back to Canada (no ethanol) things settled down. So, my question is: do you folks in the US experience this engine rattle and is there a fix that will eliminate it? I do a lot of touring in the US and would like to know if there's something I can do to eliminate the problem the next time.
     
  2. ultrat

    ultrat Senior Member Contributor

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    Hello on my 09 have not noticed a rattle.I guess i would need to compare w/ your gas i do use 93 oc.
     
  3. glider

    glider Veteran Member

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    Try to get the 93 octane, it may just do the trick. Not all stations carry it but it's worth looking.
     
  4. Hoople

    Hoople Account Removed

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    I am surprised. If you have Ion knock retard, and it is turned on, it should have masked the problem.
    You may hear a hit or two of knock, but nothing that should stand out as a "rattle".
     
  5. Subby

    Subby Active Member

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    All we could find was 91 octane and in every state the gas had 10% ethanol. But Hoople, you mentioned Ion knock retard, what is it and how do you turn it on? My ride is a 2009 Ultra, bone stock. In fact, all the bikes inour group were stock with no mods at all.
     
  6. fisherman124

    fisherman124 Active Member

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    i use the highest octane the station has without any promblems. i try to do sunoco when ever possible. i have a tend to have a heavy wrist around town and no after affects with the fuel
     
  7. Hoople

    Hoople Account Removed

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    Ion knock retard is firmware within the ECM & a special coil assembly that provides spark advance correction when severe detonation takes place in the engine. Several things can cause your preset (map) spark advance to be too great for the conditions at hand.

    In my case, my U.S. 2009 FXDL came from the factory with the Ion Knock retard system "enabled".
    You can turn it on or off yourself using a SEST or the dealership can do it with one of their diagnostic tools.

    I am sure your bike came with the sub-system turned on,, especially if bone stock. If working properly, the system will detect knock, and then back off the timing to stop it. When I was experimenting with my system, I would notice 2 or 3 hammers of knock and then the system would correct the timing to stop it.
    After reading the recorded data from the run, you can see the system kicking in when it detected severe knock.
     
  8. glider

    glider Veteran Member

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  9. Subby

    Subby Active Member

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    Thanks Hoople and thanks Glider. Since all the bikes in our group were stock and all experienced the same engine rattle under load, I'm sure it wasn't that the Ion knock retard was the problem. Chances are it was the gas because most of the symptoms disappeared once we got home and were able to get gas with no ethanol. As I said, all we could find was 91 octane. I usually run 91 octane here at home and have few problems but we don't have ethanol in the gas although our province, British Columbia) is making noises about going to 5% ethanol. We can get 94 octane at Chevron stations here so I think I'll try experimenting with it vs the 91.
     
  10. kemo

    kemo R.I.P

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    I guess there is a reason that we pay a buck more a gallon for gas.
    I think corn sqeezins should be kept for whisky not gas. Too many people around the world depend on corn for a major food source, and now there is a shortage because we have taken a quick renewable resource and made fuel from it. It is not even a good fuel, andis highly corrosive. It takes 5 gallons of corn to make a gallon of fuel
    kemo