That is spark knock (ping). Timing is too aggressive for the heat and load. Stop hitting the throttle so hard until you get it resolved or you may just blow a hole in your pistons. Doubtful octane boost will do much for you since it only raises octane ratings by points (i.e. .1, .2, .3, etc). Timing tables need to be adjusted.

 

my 2010 Forty Eight does the same thing, i thought it was just from the heat.

 

It's fuel injected, I doubt you will be able to read the plugs correctly unless it was really messed up!

It's a ping, mine does it too at 2800 and above in 4th-6th.

Correct, that's because it's in open loop longer when when the engine is cold until the engine warms up.




I believe that's my problem too, but apparently the guy who tuned mine doesn't know what he's doing! I'm going to see him Thursday AM and tell him to listen to me....Key word here is, listen.
To make sure it wasn't a fuel problem, I filled it up with Ethanol free 93 Octane. It's helped ever so slightly, so now I'm convinced it is tune related. Also, the ping is more pronounced with hotter outside air temps, I live where it' over 100*+ daily in summer! When it's cooler out, the ping is reduced..

 

Exactly, although ethanol doesn't contribute to ping (contrary to popular belief) since ethanol has an octane rating around 117. Its the final octane rating of the gas at delivery, but that's another thread entirely....

I ride with a couple of guys pretty regularly and we were coming back from a weekend trip about a week ago. Ambient air temps were 103-105. One has a 103 stage II with the 255 and the "dealer calibration" and the other is on a CVO (stock as a CVO can be) Fat Bob. Both were pinging like crazy running down the highway at 70mph in 6th. The only place they were happy was about 55-60 in 5th. I had no issues with my 105" at all. It's all in the tune (with that rare tank of "bad gas"). I might get 39 MPG while they get 42, but at least mine is running a lot happier....

 

Your buddy with the 103 Stage II and 255's is in trouble, weather or not he wants to believe it! A dealer Download is nothing more than a recalibration back to stock settings, which equates to a lean tune, 14.7 and he is running hot! Ask him how his inner right leg feels.... The only cure is a fuel management system.

 

I had that problem on a 07 Sportster,it was under warranty,they started jacking me around and I got rid of it.I still think it was the ecm that did not retard the timming under hard acceleration.

 

One of the MoCo philosophies is, if there is a problem and they don't acknowledge it, a problem doesn't exist!

 

update:
Jamie at Fuel Moto emailed me a map with revised timing this morning, that he feels should take care of the problem. I'll be uploading it tonight after work - i'll keep ya'll posted. Thanks for your help

 

uploaded the map from Fuel Moto with revised timing and it eliminated the ping I was getting!

Very pleased indeed.

This forum has been a lot of help in the past, but this particular string really put the puzzle together for me and led to a fix.

thank you all!

 

Thank you for giving us the opportunity to help out