07 wr450 jetting issues

i got a 07 wr450 i just picked up and at 3/4 steady throttle it studders bad but if you are going from no throttle to full throttle it wont studder at all...it has the ais done and the grey wire mod.....tore the carb apart today and here is what jets were in it

main-175

pilot-50

starter-65

leak-45

pilot air jet-110

and a red moose fuel screw

and it has a needle with 7 positions and the clip was right in the middle

it does this with the stock exhaust and also does it when i put the full pro circuit on....any help would be great

Unplug your TPS throttle position sensor and see if that helps.

I'm not sure where you're riding(elevation, temps) but I'd guess that the main, pilot, and needle are way too rich. I'd go to a 168 main, 48 pilot, 3rd or 2nd clip on needle, 2 turns out fuel screw. all this with the aftermarket exhaust installed. Mine doesn't stutter at any throttle position, and the TPS is connected on mine.

I used to have a 175 MJ and it would sputter heaps. Disconnecting the TPS helped when at steady speed but changing to a 170MJ and raising the clip 1 position helped heaps.

Dont change too much at once and keep track of the changes your make.

Oh and do the oring mod... I'm not sure why I rode my bike for 1 year before doing it!

Oh and do the oring mod... I'm not sure why I rode my bike for 1 year before doing it!

can you help me out with what the o ring mod is

Did you put your pipe on yet, 165(8)main, 48pilot, 65 starter,50-40 leak, needle in the 3 or 4th clip from top., You need to set the AP squirt, lift up the sub frame so you can look ito the rear of the carb.

http://www.thumpertalk.com/forum/showthread.php?t=309069

http://www.thumpertalk.com/forum/showthread.php?t=239791

http://www.thumpertalk.com/forum/attachment.php?attachmentid=5788&d=1192056593

Use a twist tie and slip 2 --- 1/4 to 3/8 o-rings over it.( i forget which size )

In the above picture PTScrew slip the two o-rings over the head of the screw and use the twist tie to gentley pull the o-rings over the back flat were the screw sits on the plastic, it will help strengthen the spring preload and give you a faster squirt.

i got a 07 wr450 i just picked up and at 3/4 steady throttle it studders bad but if you are going from no throttle to full throttle it wont studder at all...it has the ais done and the grey wire mod.....tore the carb apart today and here is what jets were in it

main-175

pilot-50

starter-65

leak-45

pilot air jet-110

and a red moose fuel screw

and it has a needle with 7 positions and the clip was right in the middle

it does this with the stock exhaust and also does it when i put the full pro circuit on....any help would be great

Hey thatraptorguy

I am in ohio too...I just rejetted my 09 and it runs perfectly...

I bought the GYTR AIS removal kit and the JD jet kit....

here are my specs

Year: 2009

Model (400 - 426 - 450): 450

Cam Timing (WR/YZ): WR

Main jet: 165

Pilot Jet: 48

PAJ: Stock

Leak Jet: 45

Starter Jet: Stock (don't know what size it is)

Fuel screw (turns out): 1.5

Needle Model/Clip position: JD Red needle 5th clip

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: Stock

Exhaust Brand: Stock (removed the little pee pee from the exhaust)

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