Long term damage on a lean motor?

Discussion in 'General Harley Davidson Topic' started by Dr. Dolittle, Mar 18, 2008.

  1. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    I tried to post this yesterday but my daughter's laptop burped and I guess it never made its way through cyberspace.

    I think I am coming to grips with a few basics from reading lots of stuff on this forum:
    1) Stock TC motors come from the factory running lean in order to meet EPA requirements.
    2) Lean makes the motor run hot - fuel actually helps cool the motor while it's running.
    3) Stage One mod lets the engine breathe better and adjustments to the fuel injection system (remap, TFI, PCIII, etc.) helps the lean condition and allows the engine to run slightly cooler.

    Sorry the buildup took so long but here's my question:

    If I leave the engine/air filter/exhaust bone stock on my Street Glide, is there a possibility of damage from running lean continuously year after year, mile after mile? Has anyone put significant miles on a totally stock motor and ended up having problems that they traced back to a too lean condition?

    Thanks!
     
  2. glider

    glider Veteran Member

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    There are many that run the bikes stock with little or no problems from a lean mixture but why run a motor hot if it runs better and is more comfortable to ride as far as heat after adding some basic parts to make it run more like it is supposed to. Just the simple things like a stage 1 and a TFI will run much better than stock and if you want some more noise a set of slip ons will do that for you. The stock 07&08 mufflers flow pretty good because of the new design and have a good sound over the previous years so they aren't a necessity to replace.

    If you rode a stock bike and then the same bike with the things mentioned above, you would see the difference then.
     
  3. Solitaree1

    Solitaree1 Banned

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    When is the last time you looked at your plugs??
    that should give you an indication of just how hot (lean) you're running.
     
  4. glider

    glider Veteran Member

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    With todays fuels and the lack of lead in them, you'll rarely see a plug that is other than white or a bit of carbon on a newer motor. Most "color" you see on a plug is from fuel additive packages.
     
  5. Solitaree1

    Solitaree1 Banned

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    I would, respectfully, disagree. The differences are much more subtle than say..back in the 60's or 70's, but I think they are still there. Particularly if one's motor is running hot enough to damage it. Which is..what I think the orginal poster was questioning. In any case...it's time to go to work...(darnit)
     
  6. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    $$$$$
    Don't relish spending money on things that aren't necessary. That's why I phrased the question the way i did - will it do any DAMAGE? As the budget allows, I will probably still do the Stage One and at least some slip ons to change the tone of the exhaust(not the volume). I just want to make sure I'm not ignoring any harm occurring to my motor, no matter how slight.
     
  7. piccupstix

    piccupstix Member

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  8. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    Nah - subtle difference here - you were implying that you HAD to do these mods and were griping about that after spending the big bucks on a new bike. I'm asking IF anyone really has to do these things to basically protect their stock motor. Shades of gray, I'll grant you!
     
  9. Ozoneman

    Ozoneman Active Member

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    I'm getting SERT and a dyno test for piece of mind. The previous owner put Sampson pipes and stage 1 with the HD download. I don't know for sure how my bike is running. I know that it pops and backfires on occasion when down shifting to stop so I'm going to pay the $400 for the SERT and $300 of dyno time to get it right.