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Latest post Tue, May 22 2018 5:35 PM by sfranta. 6 replies.
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  • Sun, May 20 2018 9:43 AM

    • Grimpy
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    • Joined on Sun, Aug 25 2013
    • Posts 3

    Lightning [li] Carb farts O-plenty @ or just off idle.

    1999 Evo,voes set @ 3.8

    Going to rewind the clock a few weeks so bear with me. 

    Purchased Dynatek 2000i several years ago, flawless, spot on performance. Crapped out on a Thursday morn & the Ozark run starts Sunday.

    In a pinch, I found a S&S(Crane) Hi-4 ing in Dallas installed following instruction to the letter except the dynamic timing procedure, finished by Sat noon. I selected mode setting #1 (SF-SS-OE curve) Carb farts right off the bat. Knowing the carb is dialed in to near perfection, I selected #0(SF-SS-race curve) & yes, I did the on/off thing 3 times for programe download. No change. So I selected the rest of the modes that were relevent to my application(#8 & 9 were KS-N/A)..No change. Back to mode #1 & advance ing module to 30deg, no farts whatsoever but pinging @ accel. Advance settings from 6 to 0 was tried with 0 yeilding best results regarding pinging(light). Went back to mode #1 & retarded timing back down to TDC (static timing per instruction) & set advance curve to #6. Carb farts coming off of "just off idle" again.Light ping under load/accel, adjust advance curve to 5 & then the JET powered,monkey navigated bike came to life with no pinging whatso ever. The Ozark run is made with no peformance issues @ cruise. Stop/go traffic was PITA. Stalling,restarting,cussing & spitting. Increased carb idle setting to stay on the top side of "carb fart universe" but the idle being to high sometimes caused dieseling @ shutdown.

    Yes, I did the low speed carb thing & NC

    Stoped by Impact Cycles in Ark & did a dynamic timing procedure & still no change. *NC.

    So my ? is, What is the timing supposed to be @idle, just off idle & a brief explanation of how voes is joined @ the hip @ this lower rpm.

    & your insight on what the hell is going on.

    Did I possibly get a POS ing? Please help.

    Grimpy who is fixing to turn into Grumpy

     

    A LEO once said " Nail that sticks up gets hammered down" Soon afterward I discovered that I'm allergic to tazers.

    A little Johnnie Walker wisdom for ya. Feel free to share.

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  • Sun, May 20 2018 10:43 AM In reply to

    • FX
    • Top 10 Contributor
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    • Joined on Sun, Mar 12 2006
    • Tonawanda NY
    • Posts 5,180
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    Re: Carb farts O-plenty @ or just off idle.

    I'm not familiar with that ignition Grimpy, but. This is an indication that the VOES may be bad or a leaking vacuum line to it. The VOES determines at what engine vacuum the ignition retards under load, to prevent pinging...It seems that you might be running retarded (I know, join the club).

    FX

    Don't force it, get a bigger hammer.

  • Sun, May 20 2018 2:22 PM In reply to

    • Grimpy
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    • Joined on Sun, Aug 25 2013
    • Posts 3

    Re: Carb farts O-plenty @ or just off idle.

    I failed to mention that I checked VOES with multimeter & it does its thing @ the mentioned vac setting. Also replaced vac line even thou the OEm line showed no leak. Did an extensive & thorough check for vac leaks using various dangerous liquids/gases. I can say with confidence that there is no vac leak. Back to the VOES. You may hit on something that I have not considered. Yeah,sure the VOES does work when external vac applied (mighty vac) but does that signal ever reach the ing under real time event? Does it even fall into the equation @ the idle RPM? Only one way to find out.

    All this "farting" began @ the intro of the S&S ing.

    My question is, Knowing what I have done already, I need another set of "eyes" to confirm w/o a doubt that it is a faulty ing & ask of anybody that may know of another "Acid test" /procedure that may reveal the direction I need to go.

    Appreciate the info FX. Going to double check that VOES circuit.

    A LEO once said " Nail that sticks up gets hammered down" Soon afterward I discovered that I'm allergic to tazers.

    A little Johnnie Walker wisdom for ya. Feel free to share.

  • Mon, May 21 2018 5:40 AM In reply to

    • FX
    • Top 10 Contributor
      Male
    • Joined on Sun, Mar 12 2006
    • Tonawanda NY
    • Posts 5,180
    • Moderator

    Re: Carb farts O-plenty @ or just off idle.

    Grimpy, I'm still leaning toward the VOES (Vacuum Operated Electronic Switch). It sounds like you tested it correctly, with vacuum attached. Are you sure you have it wired into the ignition correctly? You can look for vacuum leaks elsewhere that will effect the VOES operation...

    FX

    Don't force it, get a bigger hammer.

  • Tue, May 22 2018 10:18 AM In reply to

    Re: Carb farts O-plenty @ or just off idle.

     something else to consider: this ignition is very touchy about having a good ground. on my bike when i was running this ignition, i ran a seperate ground wire from battery negative to engine for this reason. if the ground is not adequate, it may also have something to do with why the old ignition quit. you should also change out the plug wires. if they are leaking radio waves, it can cause radio inteference around them, which can interfere with, and sometimes destroy, the ignition module. non resistor plugs can give the same problem

     

  • Tue, May 22 2018 5:25 PM In reply to

    • Grimpy
    • Not Ranked
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    • Joined on Sun, Aug 25 2013
    • Posts 3

    Re: Carb farts O-plenty @ or just off idle.

    FX

    Afew years back when I installed the Dyna200i ing I had an issue when I loaded the bike down for road trip to the mountains. The initial VOES was 2.7, below factory for a 99 FXST. Adjusted to 3.8 which is above factory but I took in account I ride heavy( I pray the ole lady doesn't see this post) sealed up VOES with rtv....problem solved.Years of excellent performance. But I'm not discounting your advise. Teardown,inspect circuit closer,verify.

    sfranta

    Plug wires were changed out with proper wires/plugs recommended by S&S,still no change. The grounding theroy seems very plausible & one I haven't considerd. As I look @ install drawing I can't see what ground goes to battery. Is it the VOES ground that goes to battery? The install instruction # is 510-0277. Single fire,single plug with VOES. You may hit on something & I would like to take further.

    Grimpy

    A LEO once said " Nail that sticks up gets hammered down" Soon afterward I discovered that I'm allergic to tazers.

    A little Johnnie Walker wisdom for ya. Feel free to share.

  • Tue, May 22 2018 5:35 PM In reply to

    Re: Carb farts O-plenty @ or just off idle.

     if i remember correctly, the main ground from battery to the frame is under the seat. i just ran a seperate 12 gauge wire from negative post to one of the starter bolts on the inner primary to make sure the engine assembly was well grounded.

     

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