First, I have searched the forum and done a ton of research on this subject before posting. I didn't find specifically what I am looking for so thanks in advance for the advice.
My 2009 WR450F has the following setup
Cam Timing (WR/YZ): Don't know
Main jet: 165
Pilot Jet: 48
Leak Jet: 55
Starter Jet: 72
Fuel screw (turns out): ?
Needle Model/Clip position: 5th clip up from the bottom
Grey Wire Mod (Y/N): Yes
TPS Connected (Y/N): Yes
Airbox Snorkel/Lid (on or off): OFF
AIS Removed (Y/N): Yes
Airfilter Brand: Twin Air
Exhaust Brand: FMF 4.1 with powerbomb header
Average Altitude: 800-1000'
Average Temperature: 60-90F
Average Humidity: 70-80
The symptoms I am trying to correct is the steady RPM stutter and backfire-popping on decel (real bad)
I have tried disconnecting the TPS and although it does make it run smoother, it still stutters pretty bad. Since I DS the bike I really need it to run smooth on pavement. I even replaced the TPS earlier this year and had no effect.
i have taken the bowl off and cleaned all the jets and every little hole I could find with carb cleaner.
I checked the exhaust front to back, put in fresh gasket, and verified no leaks. Re-packed the muffler.
Before I put the carb back on, I would greatly appreciate any advice as to what I can do to make it run better.
Again, thanks in advance!!!