gained torque lost top end

babycleatus

Member
Oct 19, 2004
31
0
I rode my kdx for two hours strait the other day, and when I stoped for a drink and left it in neutral it died, it would no longer idle as it had when it was cold. so I backed out the black air screw on the side of the carb, and this helped it idle. after it cooled down and i cranked it, it idled very high and I lost the top end hit, but gained four stroke torque. the power band is unidentifiable, it sputters on the top but runs great if you short shift it. how do yalls kdxs run, is there a noticeable top end 2-stroke hit or just torque, does yalls flatten and sputter on the top end?
 

harryhuia

Member
Nov 7, 2003
55
0
my 95 kdx200 as a very good top hit but struggles to idle. i changed this once with the air screw but then i lost my top end
 

KAY DEE EXER

~SPONSOR~
Mar 3, 2003
629
0
When was your P/V serviced last? Does it fix itself when you put the idle screw back to where it was originally?
 

babycleatus

Member
Oct 19, 2004
31
0
P/V????? power valve???? I dont know i bought it a week ago from eximport cycles in Houston, it was spotless but they left the old gas in there, still cleaning the fuel system. it doesnt look like it has ever been run or tinkered on.
 

babycleatus

Member
Oct 19, 2004
31
0
I havent turned it back all the way yet, I would think it would go back to normall but i have been trying to clean the carb lately
 

Rhodester

Member
May 17, 2003
549
0
Flattening out and sputtering on the top end (4-stroking) indicates that it's too rich on the main jet. Turning the air screw out (leaning) indicates that it was/is too rich on the pilot jet. More than 2 turns out (or so) means that it's time for the next leaner pilot. If it starts to idle high you've gone too far out on the air screw and it's too lean (when hot). The KDXs come too rich from the factory. Try 1 or 2 sizes leaner on the main and 1 size leaner on the pilot and the air screw 1 to 1 1/2 turns out for a starting point to fine tune your jetting. GENTLY turn the air screw in to the bottom (barely touch bottom) and count the turns out. Start out with new gas if its age is in doubt. Try a synthetic premix oil @ 40:1.
 

trailryder

Member
Oct 1, 2004
133
0
Baby- since this is your first bike may I suggest you buy a factory service manual for your bike and read it cover to cover. Sounds to me your having jetting problems but I'd want to take a look at those powervalves too.
 
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