Put the best fuel in it that you have available up there. You can even try different brands. Different suppliers play with the octane numbers. I won't get into great detail, but the 'number' you see on the pump is a compilation of (2) octane ratings divided by (2). That is what the R+M/2 denotes on the sticker on the pump under the number. It stands for RESEARCH octane rating, plus MOTOR octane rating divided by two. Suppliers can and do "modify' or 'adjust' the RESEARCH number to compensate for a lower MOTOR octane number. The MOTOR octane is the TRUE unbiased rating....it is what it is. No....it probably won't hurt anything IF it is just that quick one or two pings when pulling out. It won't do it any good either, as it is two separate flame fronts colliding in the cylinder in an uncontrolled burn causing the sound you hear.....it essentially like taking a hammer and beating on top of the piston. I would do whatever I could to avoid it.Wiggle2, it sounds like your bike is doing the same thing as mine. I do run at lower revs than most other Buell riders I've met and lug it a bit. Do you think it's worth worrying about? It normally doesn't ping and it's easy for me to avoid.