Hi all,

Califonia model, 2500 miles, all stock including the air filter.

Anyway, with a roll on throttle, 5th gear, from 65 mph, my bike begins to ping.

I would like to know if this is unusal.

Although the exhaust smell is fuel rich, the exhaust pipes, where they exit the head are blue (indicating a lean condition to me). The tips of the pipe look dark yet not overly rich in black soot.

Most of my riding is around town or crusing the highway at 55/ 65 mph In other words, I rarely grab a hand full of throttle.

Local HD service manager gave me a lead that it may be carbon build up in the combustion chamber.....

I purchased Redline Fuel Injector cleaner for Motorcycles as a cure. Will run eight ounces of it over the next two hundred miles (six gallons).

I have not removed the spark plugs.

When I remove the plugs 1500 miles ago they indicated a lean condition.

If I do remove the plugs today, a possible cabon ring at the very bottom of the plugs threads, may indicate the carbon build up...Yes?

I do not have a bore scope to inspect the top of the pistons.

I posted this as an aid to anyone else having a ping issue and to get a survey and feedback as to a possible cause and to receive comments.

 

A lean mixture is one of the main causes of 'roll on' detonation, as I assume you are running the correct 91+ octaine fuel.

It could also be caused by carbon buildup, type of sparkplugs used, overheating, dirty injectors, and a host of other stuff..

Here is a some good information dealing with detonation and it's cause. It's from an automobile site but much of the information applies to our bikes as well.

http://www.dnd-automotive.com/tuneup/spark-knock.htm

 

Like OFG said, there are a number of possibilities. While my 04 is carbed, I had the same issue with detonation when I rolled on WOT in 5th gear between 60 - 65 mph. I chased the problem on and off for a year going through everything, including swapping out the ICM from another Sporty. I finally became convinced that the HD ICM ignition timing map simply left a lot to be desired. I wound up replacing the stock ICM with a programmable ICM and better map, problem solved.

In your case, if you have been through the standard checks, you might want to consider a Stage 1 upgrade with a programmable ECM.

 

Have you tried buying gas from a different station?

 

Yep, changing brands and making sure you didn't get a tankful of <91 octane is always the cheapest and easiest 1st step. But, the symptoms of bad gas or octane issues will usually show up in multiple gears when rolling on WOT unless you stretched the previous gear upwards of ~4500 rpm.

If the problem can only be reproduced in 5th gear, between 60 - 65 mph, I'd suspect you have a coincidence of engine load, rpm and vacuum, placing you at a point on the timing curve that's to far advanced. This of course assumes you have eliminated other possibilities like vacuum leaks or bad Map Sensor, which could throw off the ignition advance curve.

 

Put a set of 07 Buell spark plugs in my 07 Nightster,got about 95% ping right out of it for now.

 

Good Lord all new bikes run lean if it pings in 5th at 65 then down shift!! You should try riding one of the 07 or newer Touring bikes they have a six speed and you have to ride in 5th 90% of the time.

 

My bike would ping a little during the break in period... Although it only happened when the bike was hot and stopped/idling... Once I completed the Stage 1 and switched to synthetic oil, all pinging stopped...

You have two things working against you here... 1: All newer stock HD's run lean (thanks to the f!@#ing EPA)... 2: California models run even more lean with that beautiful canister (thanks to the f!@#ing liberal CA government)....

Oops.... Did I say that?