Raising the needle

[canadian-dirtbik3r]

Ive noticed a bog in my throttle response. If read up on jetting guides and have come across two fixes. Raising the needle and tuning the airscrew. Im not much of a mechanic so i need help with this. First i will try tuning the air screw now whats the best way to do this? Is it to ride and twist the air screw or should i adjust it when im in neutral? Also i have no clue on how to adjust the height of the needle. I know how to take off that cap on the carb and access the needle but i dono how to move it up at down. Can someone give me a step by step procedure on how to raise/lower the needle. I would greatly appreciate any help! Oh yah i learned how to do donuts today :aj: but noticed the boggish throttle response and want to get it proper.

 

[SirHilton17]

Define bog...

hesitaton my ur running out of gas..
or like a sputter like there is too much gas

Raising the needle will richen ur mixture, and if it is a rich bog it will hurt you, but if its a lean bog it will help.
Raising the clip on the needle will lean out ur mixture and do the opposite of raising the needle.

also you have to determne how much throttle and rpms are on the engine when it bogs..
if it is low throttle openings/low revs i would change the piolet jet, richer or leaner what everit needs.
You can give the air screw a try, it is probably a better bet than messing with the needle, screwing the screw in will limit the air coming in, so it richens ur mixtur and out is the opposite, the stock pos it usally somewhere around 2-2.5 turns out. i think i have my 125 at 2 turns out

 

[oldfrt613]

To answer you question, to move the needle, you need to take the cap off the carb and remove the slide. Now pull the spring towards the cap with the plastic guide in the slide. Now with the spring compressed, grip the cable and push it down toward the slides and slide it out the notch. Now you can remove the retainer for the jet needle. There will be an e-ring which sets the needle height. Move it up to lean the mixture, and move it down ( towards the taper ) to richen mixture.

 

[canadian-dirtbik3r]

Well all ive noticed is a low end bog which doesnt sputter so what would that mean? Im rich on my pilot? Next time i open up the bike to high gears and high rpms ill check out how it runs. Right now my spark plug is fairly a mocha brown but i want to fix that lowend bogging. If im rich on the pilot jet how many different pilots should i get and does the #s decrease or increase on the jet? I havent took apart the carb before so how would i change my pilot jet?

 

[mxrider_1]

The air screw mainly affects low speed jetting while the needle affects mid range. I would change the pilot jet and then use the air screw to fine tune it.

 

[SirHilton17]

I would concider a bog being lean.. but thats just me

125's are not real strong in the low end...
I dont know how much experience you have riding, but if you dont have much, i am betting that you just have to get used to it... 125s arnt like 4 strokes or 250 2 strokes that make good power every where.
You will be able do jet it out, but most likely you will lose some sort of power from somewhere else...
If the jetting is somewhat correct inside the carb, the air screw will make a big difference...
From what your describing i would say your running lean.
Try somthing..
get the bike fully warmed up, put it in 1st and go slow,not to slow but not revved out, and snap the throttle back to full really quick, and if it hesitates before it revs, you are most likey lean.
If your not haveing any problems fouling plugs, yur probly not rich, so.. try turning in the air screw at 1/2 turn intervals, then ride it, and see if it goes away.
if the air screw doesnt cut it you will have to drop the float and change piolet jet sizes.

 

[canadian-dirtbik3r]

Well I do actually have problems with fouling plugs but that is usually after long deaccelerations but i have been throught quite alot for the amount of times ive been riding. I would say ive fouled around 4 plugs and rode the bike under 10 times. What would "dropping the float" be? I will try doing giving it wide open throttle in first and see what the response is like. But like you said maybe its just me not being used to the power a 125 makes. But when this god damn rain stops im going to run some tests to find out where my bikes bogs and where it sputters. What actually does "sputter" mean?