HELP! quad sounds bad...

[300EXrider02]

I have a open air box, 128main, exhuast, K&N w/outerwear, no choke and a 42 pilot jet...


I go through the gears, really hammering the throttle say down a road, and each time I shift, it makes this stutter sound as I hammer down the throttle

it pisses me off when I am going off a jump slow or fast like say in 3nd or 3rd, and want to get that extra boost off, you hit the throttle and it bog, stutters for a second, then goes good...

any sudgestions?
should I run a 40 instead of 42 pilot? or go back to stock pilot?
does it have anything to do with the air/fuel screw?

PLEASE HELP!!

[2k2-300exnj]

pilot it is an idle jet the needle might be the problem

[monkeyboy]

my tecotty soonds likk a nazkar:bandit:

[hondafox440]

Heres a simple jetting test, written by spanks over at dirtbike.com. Sounds like your pilot is a little rich.

The only way to know what jetting changes you will need is by trial-and-error. No one can give you jetting specs, because every bike is different, every rider has a different style, and jetting is totally weather dependent.

Jetting is fairly simple, and is a useful skill to learn if you ride a two-stroke and want it to perform at it's best.

Start with the pilot circuit. Warm the bike completely, and shut it off. Turn the air screw all the way in, then turn it out 1.5 turns to start. Start the engine, and turn the idle screw in until you get a slightly fast idle, or hold the throttle just barely cracked, to keep the engine idling. Turn the airscrew slowly in, and then out, until you find the point where the idle is fastest. If you end up less than 1 turn from closed, you need a larger pilot jet. If you are more than 2.5 turns from closed, you need a smaller pilot jet.

Once you have determined the correct pilot jet size, and tuned the air screw for the fastest idle, set the idle back down, and ride the bike, using closed-to-1/4 throttle transitions. Turn the air screw slightly in either direction until you find the point that gives you the best response when cracking the throttle open.

You have to constantly re-adjust the air screw to compensate for changing outdoor temps and humidity.

Now, the needle. Mark the throttle grip at 1/4 and 3/4 openings. Ride the bike between these two marks. If the bike bogs for a second before responding to throttle, lower the clip (raising the needle) a notch at a time unti the engine picks up smoothly. If the bike sputters or sounds rough when giving it throttle, raise the clip (lowering the needle) until it runs cleanly.

Last is the main jet. This is located inside the float bowl, and affects from 1/2 to full throttle. The easiest way to test it is to do a throttle-chop test. With the bike fully warmed up, find a long straight, and install a fresh plug. Start the engine, and do a full-throttle run down the straight, through all gears. As soon as the bike tops out, pull the clutch in, and kill the engine, coasting to a stop. Remove the plug, and look deep down inside the threads, at the base of the insulator. If it is white or gray, the main is too lean. If it is dark brown or black, the main is too rich. The correct color is a medium-dark mocha brown or tan.

[jgfarmsracer]

take your pilot down to a 40, main to a 130 or 132 turn the air screw out 2 1/2 turns should be a good starting place

then you just need to play with the air screw till that stuter is gone

i've put one 300 at 3 turns out and one at 1 3/4 out so with the same changes to exhaust and all that so just don't get mad at it just play