M8 Detonation
Seasoned HDF Member
Joined: May 2012
Posts: 32,934
Likes: 36,032
From: Carlsbad, CA
Are you using the recommended Octane a dealer quality fuel. Did you change the tune? If yes to either, that might be it.
Otherwise, assuming it's still in warranty, take it to the dealer.
Otherwise, assuming it's still in warranty, take it to the dealer.
I have a noise but I relate it more to dieseling. I only hear the noise when I'm rolling on the throttle. Yes I'm above 2500 RPM's, both bikes are stock. I took it to the dealer and I to was calling it detonation. He put it on the computer and didn't see anything. He did hear it but at his young age he's probably never heard dieseling like we did as kids when Unleaded first hit the streets. He's going to look into it and see if there's anything we can do.
Seasoned HDF Member
Joined: May 2008
Posts: 21,173
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From: South Carolina
If you are hearing pinging, it is detonation.
Last edited by Dan89FLSTC; Apr 5, 2017 at 04:49 AM.
Seasoned HDF Member
Joined: Jan 2006
Posts: 11,474
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From: Charleston, SC
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3rd Gear
Joined: Oct 2014
Posts: 7
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From: Parkdale
Im in Australia and our octane rating system is different than the US, but I'm using the top number here (98). I also have a breakout CVO 2014 Stage 3 which has no detonation issues with the same fuel.
I see there is an updated calibration now (723SHQ211) that has an addition field called Spark advance / Head temp! This is exactly the problem......as my M8 Stage 3 gets hot, it starts to ping its head off! Harley have obviously recognised this by adding this feature into the new calibration. It should retard the ignition 4 deg when the head temp get to 200+.
I think it has been getting worse, and I'm afraid that there is glowing damage in there. I don't know why there wasn't a dealer recall!
Anyway, Ill give it a go and let you know.
I see there is an updated calibration now (723SHQ211) that has an addition field called Spark advance / Head temp! This is exactly the problem......as my M8 Stage 3 gets hot, it starts to ping its head off! Harley have obviously recognised this by adding this feature into the new calibration. It should retard the ignition 4 deg when the head temp get to 200+.
I think it has been getting worse, and I'm afraid that there is glowing damage in there. I don't know why there wasn't a dealer recall!
Anyway, Ill give it a go and let you know.
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Joined: Dec 2005
Posts: 19,921
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From: poway
I have a noise but I relate it more to dieseling. I only hear the noise when I'm rolling on the throttle. Yes I'm above 2500 RPM's, both bikes are stock. I took it to the dealer and I to was calling it detonation. He put it on the computer and didn't see anything. He did hear it but at his young age he's probably never heard dieseling like we did as kids when Unleaded first hit the streets. He's going to look into it and see if there's anything we can do.
(sorry,, couldn't resist)
I think mine pings ever so slightly on a hard roll-on but I haven't gotten around to logging data to see. I get a lot of valve train rattle at idle when hot. Not quite as bad as my 02 RK with H290 cam but it's noticeable. Gonna try low leakdown lifters from WFO larry when I get a chance..
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Joined: Sep 2009
Posts: 2,114
Likes: 666
I believe there is a bit of sorting left in the knock system. It's new because it is a traditional speaker-type sensor that physically bolts to the engine.
In the past the system used an ion (software) system to calculate combustion quality.
We had issues with that system due to the original modeling being too far off when modding the engine.
Now we have a hardware system (similar to most cars, etc today) that measures vibration to determine combustion quality.
This system would not work on the earlier (pre-'17) engines due to the innate vibration from the engine. Now that the engine is counterbalanced in addition to rubber mounted, the MOCO feels the new anti-knock system will work better than the ion system as performance mods come on.
Time will tell how this system sorts out,
Bob
In the past the system used an ion (software) system to calculate combustion quality.
We had issues with that system due to the original modeling being too far off when modding the engine.
Now we have a hardware system (similar to most cars, etc today) that measures vibration to determine combustion quality.
This system would not work on the earlier (pre-'17) engines due to the innate vibration from the engine. Now that the engine is counterbalanced in addition to rubber mounted, the MOCO feels the new anti-knock system will work better than the ion system as performance mods come on.
Time will tell how this system sorts out,
Bob
