[joman2055]

i am posting this for a friend.

he has a 2006 CRF450X

he has an aftermarket airfilter, opened air box and he has a PC silencer on it.


his jetting specs are
170 main
red JD needle on the 3rd clip

he just installed an R&D power pump and R&D flexible fuel screw. he set the pump to where the leak would be a 60.

when we start the bike it starts up fine with the choke on but no matter how warm it is when you put the choke off it dies pretty much immediately. also, with the choke on or off giving it gas causes it to sputter and backfire.

we tried changing the pilot from a 45 to a 48 and he says that just made it worse.

[corey_lax]

where do you guys live?
whats the altitude/aveage temperatures?

[jtmach1]

I'm not expert by any means, but it might be a matter of getting the fuel screw correct.

the temp and altitude for sure plays a factor so that might help us diagnose your problem

[paul turner]

The O-Ring has gone missing from the fuel screw.

Also, red needle needs to be on the 4th clip, and 45 pilot jet.


paul

[[email protected]]

The O-Ring has gone missing from the fuel screw.

Also, red needle needs to be on the 4th clip, and 45 pilot jet

.
You're probably wondering how he knew that.
He is right, so find or buy the washer,o-ring and washer and get 'er done, then put the needle clip where the JD instructions tell you to install it.
The R&D float bowl is a nice piece of equipment but it really isn't the fix for the bike. Doug