I did my 36K maintenance back in August. It seems, but I can't tell for sure, that there may be some pinging in the engine under certain limited loads (i.e., well loaded and going up a nice incline, even at in an appropriate lower gear). The bike (2003 LT) didn't do this before. I have been using the "alternative" fuel map due to the hotter weather; but, I was doing that before. (I have the "brown wire" thing on a switch.) The gap on the plugs I installed at the 36K maintenance "seemed" a bit tight. Could that possibly be the cause? Oh, and yes, I AM using the highest octane I can buy at every gas station. I would greatly value learning from the many of you who know this marvelous machine much better than I. Thanks!!!!