BoosterPlug makes the bike stutter when cold

Discussion in 'Parallel Universe' started by Rubberbband, Nov 8, 2013.

  1. Rubberbband

    Rubberbband Adventurer

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    2010 f650gs now stutters when I snap the throttle wide open when the bike is cold. Bike acts great when warmed up but I am wondering if anyone else experiences this? It's almost like I have a choke installed now...my dirt bikes bog when choked but run great warmed up.
    #1
  2. moe.ron

    moe.ron Pig. Can. Fly.

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    Why would do that to a cold engine? I'll bet mine would do that when cold without the Booster Plug...
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  3. roger 04 rt

    roger 04 rt Long timer

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    (Disclaimer: I have three BoosterPlugs)

    I haven't read many reports of that happening but I noticed the other day that my R1150 starts just a bit better without the BoosterPlug attached. Since I'm always monitoring the mixture with my LC-1 I know that the reason is NOT that the BP made the mixture too rich. It was essentially the same, indicating that at cold start the oil temp is the main determinant for fueling.

    Here's something to think about. Without a BP, if you let your bike sit overnight, the air temp equals the oil temp. It is possible that the BMSK recognizes this air=oil temp condition and uses it in its cold-start algorithm.

    When you put a BP in, say the garage temperature was 5 degrees C. The oil temp after a night or sitting would be read as 5C but the air temp would be read as -15C. Maybe the BMSK sees this as a different starting situation.

    I'm just suggesting a possibility. I think most likely if you ride with the BP for a few tanks of fuel,the BMSK will learn around it and the condition you reported will improve.
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  4. Rubberbband

    Rubberbband Adventurer

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    I'm going to give it a few tanks of gas to assess it some more. To be honest it used to bog down a little without the booster plug when cold and I may be trying too hard to find a fault with it.

    I'm not overly concerned because Jens seems like a totally solid guy that stands behind his product. So even if I chose to remove it it would not be a big deal.

    I was just wondering if anyone else can get their bike to "bog down" with wide open throttle when cold?
    #4
  5. Wyvern

    Wyvern Long timer

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    umm ... cold engine temp or ambient ???
    yes . but why would that be an issue ?
    why would you do that anyway.
    #5
  6. Rubberbband

    Rubberbband Adventurer

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    Because the parking lot I leave has an uphill climb to the road. And then when I turn left onto the road I always floor it

    Sent from my HTC One S using Tapatalk
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  7. Wyvern

    Wyvern Long timer

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    I think we should go ride together ... LoL
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  8. Full Power

    Full Power Long timer

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    We do not apply wide open throttle to cold engines.
    There are not hills on North American roads requiring full throttle to ascend.
    #8
  9. roger 04 rt

    roger 04 rt Long timer

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    If you have or can borrow a GS-911 to creat a log file, it would be easy to see what is going on. Below is an example of a problem I'm chasing on my bike. The AFR reads lean for he first 10 seconds after ignition. And the spark advance plot shows that the rpm is building slower than normal and the advance is coming in later than normal. The data doesn't say what to replace but it did point me in the right direction.

    [​IMG]

    I tend to agree with you. 2-3 minutes of riding moderately is better for the engine.
    #9
  10. Wyvern

    Wyvern Long timer

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    Not looking to hijack or change the topic .

    Does the ecu need to be "reset" after this (perhaps other mods)
    I am familiar with "intuitive ECUs"

    could this be that simple of a fix ?
    #10
  11. itsatdm

    itsatdm Long timer

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    It will reset itself with the exception of causing the service light to come on. The ECU does seem to learn your riding style and makes some minor changes to accommodate the addition of the fuel module. The first time took a few hundred miles.

    This time after removing the battery cables for a few minutes it took less than 20 miles to adjust.
    #11
  12. Rubberbband

    Rubberbband Adventurer

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    Might have to try disconnecting the battery then...Thanks
    #12