Hi guys. I have just rejet my bike because it was too rich. Now it runs better, smoothier, no backfire. But when is cold and start it has realy high rpm at idle. I adjust the idle speed and ride it for 15-20min and when the bike gets hot and close the throttle it shuts down. Start it again with hot start (difficult to start) and the bike stays with low rmp at idle and shut down again. then I adjust the idle speed again but the rpm are not steady. when i give some throttle increase and drop down again. My bike is a WR450 2008. Before i was using the jets from the GYTR-AIS kit Main jet: 175 (GYTR-AIS) Main Air Jet: 110 (GYTR-AIS) Pilot Jet: 50 (GYTR-AIS) PAJ: 80 (stock) Leak Jet: ? from GYTR-AIS Starter Jet: 65 (stock) Fuel screw: stock Needle Model/Clip position: GYTR AIS 4th Grey Wire Mod (Y/N): Y TPS Connected (Y/N): Y Airbox Snorkel/Lid (on or off): OFF AIS Removed (Y/N): Y Airfilter Brand: Notoil sm Exhaust Brand: FMF Factory 4.1 complete, powerbomb Average Altitude: 0-1000ft Average Temp: 60-90 Now i replace the Main jet: 170 JD pilot jet: 48 JD Jet Needle: JD red - 4th and put a ZIP TY Fuel Screw 1/2 turn (still try to adjust it). Now is summer here, about 90f. Need to go to a smaller pilot-jet? Or is something else?