Oh, yes, and bike won't run right on regular gas. I get way to much knock in the mid-range. I have read articles where someone was trying to go with higher compression and wanted to know what the fuel requirements were for the 650L. I can say that on the higher compression pistons, you lose the ability to run on regular gas, and you have to run a cold spark plug - rating DPR9 to kill the knock. So, yes, the compression is way up. There certainly are technical problems, but I have most of them under control.