T-Sport: Personalizing the T Part II

Pinging

Always try the simplest things first. How could I have forgotten that classic bit of wisdom? So after all my effort to eliminate pinging by switching to Syn3, custom mapping the ignition, fine tuning the carb, and even buying an oil cooler, the principle cause of my headaches turned out to be, for the most part, the spark plug. Picture me slapping my forehead with the palm of my hand while exclaiming in my best Homer Simpson voice, "D'oh!" How did this happen?

A couple of years ago on my trip to Port Dover, one of my spark plugs developed an intermittent short. This was quickly diagnosed by my local HD dealer, and the plugs were replaced. Unfortunately, both the mechanic and I forgot why I had Screamin' Eagle split fires installed in the first place, and I ended up with HD's standard issue replacements because they were so much cheaper.

Most of my riding is

Circled is Harley's thermostat for the Jagg oil cooler.

actually quite tame, and the new plugs worked just fine. However, when I pushed the motor harder, or spent significant time on the highway where higher speeds are the norm, I started to experience pinging, and lots of it. Sunoco 94 helped somewhat, but did not eliminate this pre-ignition problem.

Last fall in a last ditch effort I decided to try out the Screamin' Eagle Platinum plugs (32997-01) despite their horrendous cost. They are specified for modified high compression motors and are one heat range cooler than stock. They would also be the first pair sold by Ottawa HD (could it be the cost?). Since installing them, I am back on the much more easily found 91 octane and the pinging, although not quite eliminated, has been significantly curtailed. In the near future, I plan to see if 94 will finally put this subject to rest.

One last comment on the Screamin' Eagle plugs: it seems that there are not too many fans of the split fires on the Internet. The spark plug of choice appears to be the NGK Iridium. The equivalent plug that I would require according to NGK technical support is the DCPR8EIX (stock number 6546). I asked Ottawa HD if they could get me a pair, but the answer was no. They have to purchase plugs in quantity, and from an economic stand point they did not want to make such a commitment if the sales were not there. Apparently even ordering small numbers of Screamin' Eagle plugs is a hassle.

I compared the price I paid for the Screamin' Eagle Platinum plugs versus what they were available for south of the border, and found that I could buy them for less than half the cost in US dollars. I felt ripped off by Harley. I will be visiting my local auto parts store about the NGKs and hope that I can do better there.

By the way, I'm still glad I had switched to Syn3 and added an oil cooler. Would have done so even without the pinging issues since built motors run hot.