Hey, guys ---- I'm having a real heck of time jetting my 2003 yam 450. I'm at 750 feet above sea level and the temp is now around 70 degrees. I'm running 93 octane pump gas and have a 168 main, 45 pilot, and the MSR fuel screw is out 2 turns. Any ideas???? It wants to stall when I chop the throttle and pull in the clutch, also the idle seems to change alot from warm engine, 150 degrees to hot engine after a moto. ANY help would be most appreciated!
2003 YZ450F carb jetting
- Thread starter mx27
- Start date
Typically called Yamabog. It has to do with the carb jetting.
Start by adjusting the fuel screw in the carb. If that does not help, then do a total rebuild of the carb, cleaning all the 1 way valves in the bowl and body, clean out the AP diagaphram, then check the timing on the AP and adjust as needed. Check the float level. After that you are down to the jets, needle and the fuel screw to fine tune it.
Start by adjusting the fuel screw in the carb. If that does not help, then do a total rebuild of the carb, cleaning all the 1 way valves in the bowl and body, clean out the AP diagaphram, then check the timing on the AP and adjust as needed. Check the float level. After that you are down to the jets, needle and the fuel screw to fine tune it.
