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1993 ys 125 power valve adjustment

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Wondering if anyone can tell me how to remove/adjust/clean the power valve on my 93 yz 125? How can i tell if the valve is in the correct position? the power is pretty boggy on low end and i think the power valve needs to be adjusted. i know some of it is the carb but id like to check the power valve to.

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do they move freely? id start by disassembling and cleaning them thouroughly ive found that oven cleaner works best for cleaning these! they can get pretty gummed up and like to stick! id start there before you look to make adjustments.... if you pull the cover there should be two allenhead bolts on the inside and one philips head on the actuator arm... remove those and slide the pin out and the valves will fall right out!

if your worried about your carb though id start there first, also check your reeds! make sure theres no gaps or fraying i had that same problem on my 00 yz125 and it was all because of a tiny crack on the reed petal! i could barely see it but someone mentioned it on here and i replaced it tinkered with air screw a little and the bike ripped instantly! didnt even have to tear into the carb or top end!

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i have cleaned the carb and all the jets and tried making adjustments to the air screw with no luck. that why it makes me believe the power valve is sticking or out of adjustment

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not being a smart a** but i told you in my first post id start by disasembling the powervalve and cleaning it with oven cleaner or some sort of degreaser... that could very well be your prob. the first paragraph in my first post will tell you what to look for when your ready to disassemble the powervalve, its very simple and when you remove the cover you will be able to tell if they are not allighned properly

and have you checked your reeds? and when is the last time you cleaned your filter? that could very well be your problem as well always rule out the simple fixes first! i always get frustrated when i tear things apart only to find out that its something so simple

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Clean air filter with still a major major bog issue so i took the pipe off to get at the power valve cover to find the most carbon i have ever seen in a pipe in my life. probably 1/4"-3/8" of carbon build up in pipe. not sure why but the last owner must have been running the oil to fuel ratio WAY off for some time now. did my best to get all of it out and it did help some....but still working on it

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There are some posts around here to help you clean all of the carbon out of the pipe. You cleaned some out, and it got better. Clean it out thoroughly and see where you are at.

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