I also need help. Pre-EVO upgrade, no issues. Ran all season, same jet happy. Fresh rebuild by respected and talented Rotax dealer.
After upgrade, won’t run past 10,500 or so. Stumbles down long straights, power out the ass from 6,500 to 9,500. He was convinced it was jetting. Jets tried were 130, 132, 127, 125, 122, 118. Nothing worked, no low end with 118. Swapped carbs with the good original. Same thing. Stumbles at 10-10500. Tried a buddies brand new ignition, coil pack, removed the pill. Power valve is definitely opening at 7500.
I miss my old engine. I ran two new series with the EVO upgrade…..MASS and Championship Enduro Series. The straightaway at Gateway sure gives you a long time to think about the “upgrade”. Everything is grounded, mounted with the new wiring harness upgrade version.
Everyone that ran Rotax this weekend had the kits still in the box…..