03 Wr450f wont start after JD jetting

[David Green]

Hi,

 

Just finished changing the jetting from stock to JD jetting. Stock is 160 and 48, JD jetting is 170 and 45 with blue needle with clip in 3rd position (just like the manual says). Also installed a new fuel screw and did the o-ring mod.

Now the bike wont start. It really tries to fire up but it only fires quickly on let say every 4th-8th stroke or so when holding the electric starter.

 

I have no idea if this is a typical lean or rich symptom. The fuel screw is 1 and1/4 turn out. Im actually not sure how the idle screw is set since i turned it alot when cleaning the carb.

 

Any suggestions?

[FORMA MOTO]

Turn the idle screw in  a bunch. You can alwasy drop it later.

 

Of course you have non-stock exhuast and airbox, to match to richer jetting, correct ?

 

Do not hold the starter down for more than 5 seconds. 20+ seconds coold down time after.

 

If it does not start in 5 seconds, it's never going to start properly, so it's a waste of time continuing to try.

 

By now you have probably flooded the motor, so with the throttle held wide open and the igniton off, kick it through a dozen times, and try and restart it using NO throttle, just choke.

 

Stock '03 jetting is 150/42 by the way... and 170 is pretty big, so see if it 'gurgles' at wide open throttle at lower rpms under load...

Edited September 23, 2016 by Krannie McKranface

[David Green]

Thanks for the reply. I will try your cure for the flooded engine as well as adjusting the idle screw. If it wont start should i try to turn the fuel screw all the way in, then try again with increments of 0,5 turns?

 

Im not quite sure what my exhaust is, but there is no restrictions in the muffler.

 

My manual says 160/48 for European 2003, as did the installed jets.

[FORMA MOTO]

Thanks for the reply. I will try your cure for the flooded engine as well as adjusting the idle screw. If it wont start should i try to turn the fuel screw all the way in, then try again with increments of 0,5 turns?

 

Im not quite sure what my exhaust is, but there is no restrictions in the muffler.

 

My manual says 160/48 for European 2003, as did the installed jets.

 

 Ah, Euro will be different, yes. 

[David Green]

Today it started right up!

I let i sit over night, fully charged the battery, turned the idle screw all the way in, did your trick with full throttle no ignition, and voila. As expected i had to adjust the idle down, but it now idles fine.

 

Thanks for the help!