The KM unit was intended for the YS but works fine on all IC engines. I notice no performance loss but then again I haven't actually measured if a difference in rpm exists. Just from feel in the air, no difference except ever so slightly mellower exhaust note. My little gizmo produces similar results.

BTW can anyone open the attachments in my posts? I can't for whatever reason. These originally posted properly and then RCU put in attachment links which don't open for me. Weird