That the same jetting in my 93 RMX, I take it your on the oem size needle. I have to run 100 octane gas cut 50/50 with mobile super to stop the death rattle. I had FMF port my jug and cut the head. I am getting around 240psi after 20 minutes of break in. FMF told me years ago to go to a thinner needle to if it was rattleing. I did but it seemed to flat with the thinner one in the carb. I got oil on the rear fender. In the end. It was oem needle and buy 100 octaune gas. Its like 3.29 a gallon. makes for a pain and extra expense, But I never toasted a piston or needed to put a lower end in it.