Spark Knock MLVHD

[Wookie3011]

2016 FLSTFBS 124", 10.6:1, getting a decent amount of "perceived" spark knock through HD ion sensing. At no time am I hearing it BUT I do have the borzilla so... I'm using MLVHD and have general areas in histogram of events averaged in a RPM Range 3300-6450 at 75KPA-104KPA. I have 2 questions. Why am I hitting 6450 RPM when my Rev limiter is set to 6200? How much timing is a little timing if pulled. I did go get the Vrod plugs to see if going colder and gapped at .035 would lesson the Knock. I also have some VP Racing octanium I've thought about using to bring my octane up.my thought was if it is indeed spark knock that by raising my octane level, I should see less knock events to prove out if it is indeed real events. I have Hella hits below 50 KPA also. I'm just wondering how trustworthy is the ion sensing when the algorithm that was used to create it had far different parameters than what currently resides in its place.  Thanks

[Wookie3011]

So if I'm understanding it correctly. When adaptive knock retard is selected in Tune, or turned on. this is my long term values and is effectively adapting or storing these events and retarding the timing over a undetermined amount of time and decays. If all the tables are set to zero am I pulling timing through adaptive but not learning because the short term is off or zeroed? In other words is it pulling timing repeatedly because it's not set correctly to learn? What is a small amount to pull in effected areas or should I set my short term tables up to learn?

[harpwrench]

I've gapped the plugs on my bikes at .030" for years to get around false knock activity, no harm and they make good power/mileage. Right now running an 11:1 117" and an 11.8:1 107".

[hrdtail78]

I have Hella hits below 50 KPA also. I'm just wondering how trustworthy is the ion sensing when the algorithm that was used to create it had far different parameters than what currently resides in its place.  Thanks

If the adaptive is zero'd.  It should not store and should not remove ignition timing because it has learned.  The short term spark knock will still pull timing if it see knock.  But it has to see the knock to pull it.  It will pull this timing when it see the ecm react to knock but does not store or remember it.

I would look into how you calibration is set up.  Look how knock is set up.  The perimeters allows minimum KPA and RPM.  If you are getting spark activity under these.  Why? 

I also like .032-.030 for higher compression.  I have had to go to .020 to get a constant spark.  Give it what it wants.

[Wookie3011]

Ok ill try all those suggestions. It does within a matter of seconds add back the retard event. I also will be changing the SE wires back to stock. It's to bad HD chose to use ion as it's tied to the coil. It would be nice to step up the ignition on these bikes for higher end builds. I know the difference it can make on a V8. I'll let you know how it works out.