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throtle responce

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when i rip the throtle on my drz 125 it bogs then takes off . i had a 105 jet in it at first but i've gone up to a 110 all of the free mods are done and i have a k&n air filter and a yoshi pipe. i tried the neddle shim mod even and nothing changed with the 105 or 110 any ideas ? :thumbsup::thumbsup:

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It's not a main jet issue. That kind of roll-on bog is more related to the pilot system and the needle. I would guess that you need to richen the pilot. Remove the brass plug over the pilot screw and adjust it out. If you go more than 3 turns out without any improvement, go up one size on the pilot jet.

The needle dominates from 1/4 to 3/4 throttle. Raising the needle will richen it.

Those are just my guesses as to what will help, without being there and actually seeing it run.

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i've already gone up one jet on the pilot and have my brass plug removed . i have that screw 2 1/2 turns out should i go more ? i'm also about 900 feet above sea levle if this helps .

:thumbsup:

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To dial in the pilot system, use the "quick return to idle" method. Basically, you run the system as lean as you can, but have it drop down to a nice idle when the throttle is let go. If you lean it out too much, it will not drop down to idle very quickly, but rather, hunt around before dropping into a nice idle.

I didn't know that you had already gone up on the pilot jet. It could be lean or rich at this point. But do the quick return to idle test. If your bike is dropping down to idle nicely, keep leaning it out until it won't drop down very well. You lean it by turning the screw in. If you have gone all the way in and it is still dropping down nicely, go smaller on the pilot jet. Then you can richen it from there to get a nice quick return to idle.

I always try to get the pilot right first. Then I work on the main jet with wide open throttle. Finally, I work on the needle position (the clip position on most carbs) for the mid throttle response. If the pilot and main are not right, your work on the needle will be wasted until they are.

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i turned the screw in all the way and it seemed to get better so i'll go down a jet and see if it gets better :thumbsup: thanks!

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it didnt get better it makes it bog off an idle now :thumbsup: my freind is a small engine micanic he tried last night to set it up going from stock on the pilot up three and stock on the main up four and every combination he could think of but nothing seemes to work :thumbsdn:and yes this guy knows what he's doing he re jets evey bodys bike in town :

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There is a third adjustable element: the needle. The main jet only affects WOT, not bog off idle. Bog off idle is affected by the transition from the pilot system to the needle. If your pilot is good, then you need to look at the needle. Unfortunately, Suzuki doesn't make their needle adjustable. However, the Yamaha TTR-125 uses the same carb, but has an adjustable needle. You might want to get it.

Of course there might be other problems, like the float level. If you get tired of messing with it, I have the stock carb that came off my DR-Z125L when I upgraded to a PE-24 carb that I could part with. Mine has the TTR-125 needle in it.

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when i rip the throtle on my drz 125 it bogs then takes off . i had a 105 jet in it at first but i've gone up to a 110 all of the free mods are done and i have a k&n air filter and a yoshi pipe. i tried the neddle shim mod even and nothing changed with the 105 or 110 any ideas ? :thumbsup::thumbsup:

You didn't say if you raised or lowered the needle?

You are running too rich, nonetheless.

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