I took my raptor out for the first long ride since I got it running with my motor, and when I run it really hard then start cruising it starts cutting out and popping a little, then it just takes off. It also does this if I cruise in fifth at about 50 mph or more at the same rpm for a while. Then after the bike starts getting hot after riding for a while when I give it gas it does this as well. could I be having an ignition problem, can the stock not keep up with the new motor. My jetting is 190 and 195 mains with 27.5 pilots, and needles in the third clip.(I have moved them around some and it didn't help.) I also think my mains are right because it was running lean with them then yamaha adjusted my fuel screws so that the mixtures were right. the hooked up an o2 sensor when they did this to make sure air fuel ratio was right. Any Ideas, thanks

 

The mixture screws only effect idle mixture, its not gonna change the main or midrange. The cutting out and popping are symptoms of lean. If you pull the choke on, does the cutting out and poping stop? If so then you know for sure the problem is carburation and not electrical.