Today, all of a sudden, I notice some pinging/knocking under heavy acceleration. I know that a little bit of "spark knock" or pinging is common with early electronically controlled engines in cars, but being a newbie to Harleys and motorcycling in general, I'm worried. The knocking is evident at most engine speeds, in any gear, when I open the throttle abruptly or accelerate under heavy load (such as going uphill). At steady speeds, or light acceleration, there is no problem. I'm pretty sure this hasn't happened before.

My bike is a 2005 FXDI and has about 1450mi on the clock. I had the 1000 mi service done a week ago and I am wondering if they messed something up.

My concerns are as following:

-They replaced the plugs. Is it possible that they used a plug with a lower heat range than stock?

-Do they adjust the timing during the 1000 mi service?

-Maybe they didn't torque down the air cleaner when they checked it and I have an induction leak?

-There is a local law where I live (Pima Co., AZ) That gasoline sold between about this time of year and the end of March? must be oxygenated. Can this affect combustion characteristics in a motorcycle engine?

-Maybe I'm running the bike too hard and I broke something?

I would greatly appreciate any thoughts on this matter.

Thanks,
Scorpion

 

I have had problems with HD platnum plugs and knock, but would also suspect bad (low octane) gas. Install a set of stock HD plugs and ride it. If the problem doesn't go away, run the current tank of gas down and fuel it up a a different station (one that is reputable). I have gone as far as going to a service station and complaining about their premium. Usually we get you some free gas!

 

A colder plug should not cause pinging. Check the number on the plug, it should show the stock number (6r12)

No timing adjustments are done on the TC engines. It is all handled by the ECM as part of a map.

If the air claener wasn't torqued down, you would know it .

I would try a different gas station to see if it was the gas itself.

 

I would suspect bad gas first. I would add a little octane booster.

 

Would not be the first time a fuel tank driver dumped regular in the premium tank! ; )

 

How do you hear pinging while driving? What does it sound like.