1999 KDX220 Throttle Response

[dirtdadof4]

Hi everyone another newbie here. I have recently acquired a new to me 1999 KDX220. I have taken a look at a few things so far and have found the plug is a NGK br7es, the pilot jet is 48, the main jet is 160, I think it has boyesen 607's on the factory block, fmf pipe (not sure which one) and silencer (tds-3?), airbox lid removed. The bike will not idle and on the low end the throttle response is very sluggish. I feel like I am turning the throttle way more than the bike is going. Where should I start. PS: Not sure what position the needle clip is in, I cannot figure out how to get the needle out of the slide. My factory service manual has not come in yet. Thanks!

 

[cornishwrecker220]

kdx`s spark plug is ngk br8es & not 7es..pilot jet 42, main jet 145/148 needle clip 2nd notch from the top air screw 1.5 turns out ..i ran these settings on my std 220 carb with the airbox snorkle removed & a fuel mix of 40.1 ..i am at sea level.. sounds like your settings are for a 200 carb which is a 35mm (220`s a 33mm) you can identify by measureing the bore inner diametre (nearest the reed cage) to remove the needle from the slide you need to remove the top of the carb,remove the throttle spring & cable) undo the small 8mm nut inside the slide (which the throttle cable fixes to) middle clip possition is standard raiseing the needle (toward the top) leans it, lower richens..try 2nd pos from the top ride & report back. :)

 

[dirtdadof4]

I measured the bore of my carb and researched the serial number online to find it is indeed a carb from a kdx200. I also pulled the reed block out to find the reeds on one side of it flexed open a little (I am sure it is open farther than the .2mm service limit quoted in the manual). Since the carb is the 35mm does my jetting sound closer (48 pilot, 160 main)? Could the open reed be causing the sluggish throttle response off the bottom?

 

[cornishwrecker220]

your jetting is way too rich for the 220...i have a 35mm carb from a 200 on my 220..my settings are as follows..main jet 152-155 (this is riding at sea level & with the airbox snorkle removed + x3 small uni filters installed in the top of the lid for extra air )..pilot jet is 42..you must use the needle from the 220 & clip in the middle position (id number for the 220 needle is R1173L check you have the 220 not the 200 needle ) air screw between 1.5 turns give or take..i run 40.1 mix..i also run the boysen rad valve on my 220..it works well for me, some like the v force3 block..my 220 pulls really strong with this set up..your jetting along with the reeds you are running seem to be causing the bike to run rich....do the above jetting ( & fit new reeds if $ is tight) along with a ngk br8es plug & go from there.