Union 76 sells 100 octane? I wonder if it is the same as BP's Spirits 100. Is the 100 octane MON or RON? (motor octane or research octane). I know Spirits is 100 RON which comes around to sometihng like 95 MON. Which does wonders in running the KX, cause the jetting does not change much. I will say that running VP racing fuels has changed my jetting, which in my case has richened the entire band. Using Spirits did little richening, but was noticeable.