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06 125 stuck throttle...please help!

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i went on my second ride on my new top end and 3 times throughout the ride the throttle got stuck open, barely avoided a really high speed crash into some trees. the throttle tube itself was definitely not stuck, the motion of it is fine. I am going to pull the carb apart and lube the slide, but is there anything else that i should do? i would imagine it is due to the slide sticking from the carb cleaner i used on it but i'd like to make sure so i dont have a bad accident. it happened randomly 3 times in about 22 miles. I'm running a 410 main and 40 pilot, but i'm going to get a 35 and 37.5 because it is rich on the bottom. Could this be jetting related?

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Jesus this happened to me before I did my top end. Once when just starting the bike up on the stand (NO kill switch installed on either occasion) it went to the highest possible rpm but the tube was fine. We figured that the slide must have gotten stuck. Didn't touch it until I got to my friends house we took the slide out and re-installed it. He also said the cable was routed wrong and re-routed it himself but later I noticed that his routing was still wrong. He went over the coolant and spark hoses when it's supposed to be under. Don't know how much of a difference that makes.

Also my complete throttle tube/housing/and cable was atleast 7 years old and not lubed, along with the mis-routed cable.

The second occasion I was at the track and had been riding for a couple hrs. (not straight but off and on) So I fired the bike up and got out there. Luckily, I was on a uphill straight away and in the middle of a stand up wheelie, about 30-40% of the way up the throttle stuck to the highest possible RPM. Rode it for about half a second once it reached good speed and vertical. Bailed off the back and watched the bike do a literal back flip and simultaneously rip off the rear fender. It landed still WFO throttle...Tire was raging. My buddy grabbed the bike, held the brake, and dumped the clutch and somehow killed it. (Still no kill switch installed) although I think when it has this much air and fuel coming in the kill switch will NOT kill the bike anyway.

We've replaced my entire throttle assembly: tube/housing/cable and made sure it was routed perfectly and it hasn't done it since. Everyone and their bro on this forum was telling me I had an air leak, but honestly feel like that is way over-diagnosed on this board as a lack of facts present, just simple part of getting answers on the internet. I don't think it's possible to have a leak big enough to cause a WFO top RPM situation. I personally think it had to be something in the slide/needle/throttle assembly getting stuck OR if it is a leak must be somewhere in the intake.

There was another member who had this exact problem and found out his intake boot that connects to his carb had a huge rip in it...

We literally just finished my rebuild friday night, but we found a crack in one of my stock reeds, so that could have been it. Still confused about that one. We replaced ALL the major gaskets and o-rings and throttle assembly, so it's hard to say what it could have been, but it's near impossible to try and legitimately ride and get better without having to worry if your bike is going to rage out on you. Check EVERYTHING and if you find something be sure to report back.

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i had an 02 kx125 that the throttle got stuck for a split second a few times. ended up finding the the needle in the carb was slightly bent and it was hanging up on an edge in the carb. it wont hurt to check that:thumbsup:

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Not really jetting related when the slide is sticking to its mantel.

thanks for the help everyone (except this guy^). I did route a wire from an hour meter through the grouping of cables so maybe i twisted something around or zip tied a cable too tight. One more thing to check for, i appreciate the help. i'll be digging into it tomorrow.

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