Hey all,

I'm getting a rich condition stumble in my throttle between 1/8 and 1/4 and a very slight backfire on decell.

Would it be best to lean out the A/F Mixture screw or drop the needles down a position (raise the clip)?

Other than that, she runs real strong at 8000-9000 ft.

Current Settings:

A/F 3 turns out

Dynojet Mains: dj142, dj144

Dynojet needles on groove #4 from top.

Thanks,

Mark

 

Does your headpipes glow when idling? What does your plug look like after the machine idles for a short period?

 

No glow on the headpipe. The plug is black (rich) after idle.

Mark

 

Yep, definately rich. Adjust the air/fuel mixture screws in to about 1 turn out each, then check the plug after idling a while. You still want a slightly rich condition at idle too help prevent the carbs from blowing off. I would'nt mess with the needles until the plug is slightly rich at idle and the problem still exists.

 

airraptor, he shouldn't need to change his needles and mains since they don't come into play until you get more than 1/4 throttle (mains at 3/5 to 3/4 throttle). Since he specifically says 1/8 to 1/4, he needs to play with the a/f mix screws. I would try turning them back to 2 turns out.