Hi All
Here?s my stats; 2000 KX500, Pingel petcock, 5/16 fuel line, rebuilt carb, float height set to 16mm and verified with homemade fuel level tube thingey, clean air filter, pilot 55, air screw 1? turns out, DEF jet needle in the 2 position, 170 main, it?s a little rich for now, but will adjust after I get the idle/needle jetting right. Elevation 1400 to 2,000 feet, temp?
My thinking at the time was ?I got the pilot jet dialed in so on to the needle diameter?. First it had a N89D, way too lean just above idle and way too rich between ? to ? throttle! Bike only ran good at WOT. Couldn?t find data on this part number so I switched to Sudco as they have a nice chart that explains what the numbers mean and at $5.25 a piece who would argue. They recommended a DGH; Bull?s-eye, HUGE improvement! Bike never ran so good but surging was also huge. As soon as I?d chop the throttle bike would go into the ?surge mode? maybe 15 times before enough speed was lost and the motor was back to idle. But I new I was on the right track as performance was unbelievable, (I hope you believe me). Next; 58 pilot. Way too rich at idle with 3 ? turn out on the air screw and it didn?t? help the surging at all; switched back to 55 and 1 ? turns out. Next; went smaller in the needle diameter from the DGH to a DGG. This cut the surging in half! That inspired me to again go to a smaller diameter needle. Only problem is no one makes a DGF, had to go with a DEF to get the next size smaller diameter. While this is one step smaller in diameter, it is also two clip position shorter in the functional L1 length. So what-the-heck I thought I would try it any way. Installed it in the middle position, (3), and went riding. Surging was reduced but not as dramatically as the ?DGH to DGG? needle change. Also caused bike to start running rich, (rough), in the 1/3 throttle range and a drop in needle position helped some but still feels like it?s too rich. Okay that?s where jetting is at today and I?m planning to drop the needle again to the one position, (hope it doesn?t need to drop further as I?m out of position). Are you still with me? My question is what needle are you running on your stock bike? Gowen and KXcam22 helped me out by answering a question I had in another topic, ?who makes custom needles?, answer; JD jetting. But what got my curiosity was a reply that I?m out there on the jetting and the fact that the direction I?m headed is running out of needles.