Gen 3.5 Drop In Cruising Gas Mileage

Discussion in 'TFI Settings' started by Dr. Dolittle, Nov 3, 2010.

  1. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    Now that I have my horn fixed, I can address the other situation that's been bugging me since returning from Biketoberfest.

    Riding home on I-75 at a steady 75 to 80 MPH (around 2800RPM in 6th gear) my mileage was only around 35 MPG. This is a drop of at least 10 MPG from when my bike was stock. I have SE slip ons and a HD Stage I air cleaner along with my Gen 3.5 TFI. I was riding solo with no bad headwinds and pretty light load since my wife was following behind in the car.

    Current TFI settings, as per my phone conversation with Chris several months ago, is 3 1/2 - 3 - 3 - off - 4 - 4 1/2.

    Are these mileage numbers about what I should expect now on a 2008 FLHX or should I do some adjusting?
     
  2. Jack Klarich

    Jack Klarich Expert Member

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    Doc, IMO the rotten gas we are stuck with is not giving us enough burn time and BTU because of the alcohol so power and mileage will go down, Capital Jack:s
     
  3. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    I see the theory behind that. But.....10 MPG !?!?!
     
  4. glider

    glider Veteran Member

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    Doc

    Lower pot #2 to around 1 or 1+:s
     
  5. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    I'll have to go back and reread the instructions for the GEN 3.5 but I thought anything below a 2 was leaner than stock. Is it OK to run with less fuel in this regime (pot #2) in order to boost mileage?

    Thanks!

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    Wow - just went to the website for the Dobeck EJK GEN 3.5 TFI and here's what they recommend for a 2008-2009 HD Touring bike with a typical Stage I:

    5 - 5 - 4 1/2 - 3 1/2 - 4 1/2 - 4 1/2

    Wonder what your mileage would be with those settings?
     
    Last edited: Nov 3, 2010
  6. Hoople

    Hoople Account Removed

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    Humm :s
     
  7. glider

    glider Veteran Member

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    The gen 3 is a bit different than the previous ones but the the second setting is the accelerator pump function and any setting other than "0" on any of the first 3 settings is adding fuel over and above the base map in the ECM. I don't believe you can remove any fuel regardless of the setting you use.
    Lowering the second setting (accel pump feature) will reduce fuel consumption without noticeably reducing performance. This function increases the pulse width of the injectors each time you twist the throttle so by lowering the setting, it will increase the MPG.:D

    Right Hoop? :D
     
  8. Breeze3at

    Breeze3at Well-Known Member

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    I can't help with the Gen3 data, as my TFI is the older model. My '07 E.G.Classic has S.E. slip ons, and S.E. air filter. I weigh 225 and always carry avg. of 20 lbs. in the bags. The 10 tanks of fuel before the TFI resulted in 42.4 mpg average. The 10 tanks since the TFI resulted in 38.8 mpg. For the performance gain, I'm quite satisfied with the 3 mpg loss. Most of my riding is cruising backroads (5th @ less than 3,000) or Interstate in 6th. Even though each bike/rider mpg will vary, yours dropped too much IMO.
    Don't put too much worry on the data from 1 or 2 tanks of gas. Track several to get reliable figures.
     
  9. Hoople

    Hoople Account Removed

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    Doc, Don't just look at those clock positions and hold to them. Those are really starting points. You need to understand what each pot REPRESENTS along with each pots responsible RPM band.

    Once you understand what each pot represents, you can look at the type of riding you do, look at fuel consumption and adjust accordingly.

    If the above settings were the perfect setting for ALL 2008-2009 touring bikes, they would be Fixed resistors and not adjustable pots.:)

    What's the part number of the model you have. I want to see what bands/ pots do.
     
  10. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    Here's the link to the page I was referring to. Part number at the top of the page.

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