CRF450R and X 07 problem

[Prodigy411]

I have a crf450 R with main 170 and pilot 45, runs great but doesn't want to

start with the choke on.

I also have a crf 450X with the same jetting and runs great only when the engine is cold I dont have any power to 1/4 of the throtle. When the engine is warm the problem disapears.?

please help

Greetz Prodigy

[Dillier23]

Temperature? Elevation? I would think a 48 pilot and an adjustable fuel screw will help with both bikes.

[450xbomb]

I highly recommend an adjustable fuel screw. I run a R&D and love it. It makes my 450x run great no matter what the conditions. Its easily adjustable since its hooked to a cable and relocated for easy access.

[450XJimDirt]

+1 ?

I have one on my 450X(really helps because of the starter in the way)

and on my 450R , makes adjustments way easier , and you can adjust it while sitting on the bike !

[Prodigy411]

Sealevel and 15 to 25 degrees celsius.

Got a r&d flexjet on the R, with the choke on and the hotstart in it will start, so I have to go leaner with the fuelscrew?

[GTXR]

If you set your fuel screw correctly, warmed up engine and at idle. You should turn it in until you hear the engine start to stutter or change rpm and then turn it out until it does the same thing. Set it at the middle of those turns. If your fuel screw does nothing? Try setting your main jet needle down one clip. Hope this helps?