Hey Pablo Sorry to bother you, but I thought you could help. My 66cc is doing very well, but after I ride I chop plug to see how its burning. I've got 400 mile on this engine and it has always been a good chocolate color. I took out other day a few miles and checked plug after ride. The plug (NGK B6) was snow white in center. So, bike still idled well, ran out well, but white>? Confused? I've picked bike apart trying to find a air leak. Bike runs as well as it ever has still???????? Glen PS- Someone said when they burn perfect, they self clean? I've always used Amsoil synthetic also.......................... Thanks?