The dreaded PINING on the 103!
Road Captain
Joined: Nov 2011
Posts: 547
Likes: 0
From: Illinois Corn Desert
Not exactly. Detonation is an explosion someplace in the chamber that takes place separately from the desired burn wave that powers the engine. It's like a clandestine bomb going off. Timing that is too far advanced can be the cause. But more than likely on a late model EFI Harley it's the result of heat caused by running too lean. There's a long technical explanation as to the why's of this. One cure is to bump the fuel a little so that the engine's combustion chamber runs cooler, and with more power. Retarding the timing can cure a problem where detonation happens at or near WOT. But high heat as a result of running lean will result in low level detonation even at steady throttle. The engine makes faint plink plink plink sound. Retarding the timing for this kind of problem might even generate more heat and cut your power to boot. A good tuner can pretty much eliminate this kind of problem.
So Xieds MAY help and or higher octane fuel MAY help....right? Retarding the spark timing with piston stroke/position won't really help if it is related/caused by the high internal heat. A spontaneous and ill-timed detonation of the "air/fuel cloud" in the cylinder is what is occuring?
Last edited by Mark5; Nov 12, 2012 at 07:09 PM. Reason: spelling
Extreme HDF Member
Joined: Dec 2007
Posts: 13,402
Likes: 941
From: Illinois
How come my 10 Ultra TC96, 12 RGC TC103 and my 12 RGC CVO 110 stock bikes do not ping and I run 89 octane in them?
Could it be: A I don't lug the motors.
B I periodically (every 3K) treat the motor for carbon removal.
C I don't do WOT launches or try to do a wheelie.
D I'm deaf
E All of the above
Could it be: A I don't lug the motors.
B I periodically (every 3K) treat the motor for carbon removal.
C I don't do WOT launches or try to do a wheelie.
D I'm deaf
E All of the above
Not exactly. Detonation is an explosion someplace in the chamber that takes place separately from the desired burn wave that powers the engine. It's like a clandestine bomb going off. Timing that is too far advanced can be the cause. But more than likely on a late model EFI Harley it's the result of heat caused by running too lean. There's a long technical explanation as to the why's of this. One cure is to bump the fuel a little so that the engine's combustion chamber runs cooler, and with more power. Retarding the timing can cure a problem where detonation happens at or near WOT. But high heat as a result of running lean will result in low level detonation even at steady throttle. The engine makes faint plink plink plink sound. Retarding the timing for this kind of problem might even generate more heat and cut your power to boot. A good tuner can pretty much eliminate this kind of problem.
Outstanding HDF Member
Joined: Dec 2008
Posts: 2,007
Likes: 353
From: Ohio
So Xieds MAY help and or higher octane fuel MAY help....right? Retarding the spark timing with piston stroke/position won't really help if it is related/caused by the high internal heat. A spontaneous and ill-timed detonation of the "air/fuel cloud" in the cylinder is what is occuring?
Cruiser
Joined: Jun 2010
Posts: 135
Likes: 0
From: Nebraska
Have a 11 SG with a 103, V&H true duel header pipes, Rinehart 4 inch slip ons, a S&S single bore tuned induction and the stock ECM with no downloads. Run it on E10 or E15 gas and bike runs great. No pinging, great power, plugs look great. Never had any problems in the 12k i've got on her.
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Joe Kucinski
Road Captain
Joined: May 2009
Posts: 505
Likes: 2
Sycle1 - it may be the way octane is measured. Here in the UK we use the RON measure which gives a higher reading. I usually put 99 or 97 octane in my bikes but you can get 95 and 93. The States uses a reading called MON which apparently is a better "real life" measure, the scores are lower by several points. I think what is 87 MON is about 93 RON and 91 MON is probably around 97 RON. Don't know what you use in Oz but if you can get 98 it is likely to be a RON score.
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,148
Likes: 6,171
From: SE Michigan
Have a 11 SG with a 103, V&H true duel header pipes, Rinehart 4 inch slip ons, a S&S single bore tuned induction and the stock ECM with no downloads. Run it on E10 or E15 gas and bike runs great. No pinging, great power, plugs look great. Never had any problems in the 12k i've got on her.