pinging

Discussion in 'Dyna Models' started by Dyno, Sep 29, 2013.

  1. Dyno

    Dyno Member

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    Have an 08 superglide purchased new and like most of us on here gets the best of care. had a stage 1 done at 1000(SE air cleaner,SE tuner,V&H slip ons) miles and everything was good till about 6000 miles. Pinging when cracking the throttle in 4th or 5th(tink,tink sound).Changed plugs SE plugs I used Harley fuel additive drained fuel tank fresh fuel, no change. my next step was to change out plugs went one step colder(ngk plugs) and now am trying starbrite fuel additive and have done a lot of reading on using the pro tuner software,i have made some changes in acouple of tests(minor to AF,VE,and Retard timing a degree) last flash seems to have quieted it down a lot and unlike the other flash has not lost any HP. I have not changed anything when this occurred same fuel from same station (93 octane) no other mods were performed. One thing I did today took out plugs and I used inspection camera and noticed carbon on top of both pistons, some flaking on top maybe additive working? I have heard this motor is sensitive to increase in compression? could this carbon buildup cause the pinging problem?
     
  2. Hoople

    Hoople Account Removed

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    Before you do anything, go into the Super Tuner software and see if the "knock retard" subsystem is enabled.
    It should be enabled. If you look at some of the numbers for stock advance curves, they are way over the top.
     
  3. Jack Klarich

    Jack Klarich Expert Member

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    The carbon could be causing pre ignition and or detonation, the SE plugs are famous for that, NGK plugs will do the same thing if too much carbon is present, it creates hot spots that retain heat and can flash over ignition when you do not want it
     
  4. Dyno

    Dyno Member

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    knock retard is enabled took af from 14.6 to 14.1, increased ve 2% and dropped timing back 1.25 deg from 1500 rpm to 5000rpm across the board. does run good now very little ping if any what plugs would you suggest I think I am on the right trac but any tweeking would be appreciated,also when I looked at the map the dealer used it was the map that came with the SE tuner no tweeking at all,it was like after they got the money it started up(the bike) and they wanted it out of there.
     
  5. Hoople

    Hoople Account Removed

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    Duck tape the VCI to the bars and make a recording run. Ride the bike harder in order to hear the ping. Play back the recording on your laptop at home and compare when you heard the ping to the VCI playback in order to confirm "when and if" knock retard was kicking in. You can flag or time stamp a point in a VCI recording by blipping the throttle 3 times instead of looking at a watch and writing all the times down.

    This will tell you several important things. It will confirm that what you heard is in fact detonation, and it also tells you which cylinder (if not both) the detonation is in. Instead of making global changes to the maps, it also tells you which specific map cells needs to be targeted.

    What's the file number of the download your working with.
    Very strange it just started doing this at 6000 miles. If your advance curves are right on the edge, seasonal fuel additives / brand / moisture in underground tanks or real % of alky could be enough to push you over the edge.
    I see it every so often on my bike until I buy new fuel at a different station.
     
  6. Dyno

    Dyno Member

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    Here is the file and # I used as the base map,'All Market' 1580 SE A/C & Race Exhaust Stk Stk Stk 25deg 27709-06 176AE106, also this is what the dealer had loaded in the bike. I will try to ride this weekend and record as you suggested and I will do exactly as you said and post info,
    Thank You,
    Don
     
  7. Hoople

    Hoople Account Removed

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    176AE106 is the same base file I am using. A very large portion of that fuel map is closed loop and the advance curves have a ton of advance at mid cruise speeds.

    I am pretty sure the reason for all the spark advance is to reduce emissions and to squeeze every last ounce of fuel mileage out of a gallon of fuel. The programmers completely depend on the knock retard system to keep the engine together. I see no way for an engine not to knock while using spark advance numbers like 38,41,44,45 and on top of that being closed loop.

    Yes the system does work and it will pull back the timing but it takes a second or two for the system to react. The system sees detonation from the spark line of the spark gap. So you must first have detonation take place before it can be corrected. You will hear a couple of hits of detonation before the system can react & pull back the timing. I didn't like hearing those few hits of detonation every time I cracked the throttle so I pulled out a good 6 degrees in a few cells. The more advance the system has to pull out, the longer it takes in time to perform that task. I read somewhere it pulls out advance in 2 degree steps, so 6 degrees would take alot more time than 2 degrees.

    Even after making the values more realistic, I didn't see any reduction in fuel mileage that was worth talking about. The performance is the same and I no longer have that terrible knocking sound except on very rare occasion and I have to lay down on the tank to really hear it. And since it's only correcting maybe 2 degrees instead of 6 or 8, it's reaction time is quicker than before..

    The SE tuner is a powerful tool and there's no better Dyno than public roads..