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High reving and fouled spark plug problems

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I have a 2005 suzuki rm 125 and it seems to keep fouling my spark plugs and reving uncontrollably as soon as i kick it on and it will continue to rev as high as possible and wont go down..  I have a brand new top end in it and i have cleaned the carb completely. I put the needle on the last position to hopefully try and lean the mixture out but nothing changed my spark plug is still fouling wet. Please help. And for the reving i have tried adjusting the air screw nothing happened. My throttle cable has some damage to it could that be why its reving high? Feedback would be really appreciated.

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have you tried winding the idle screw out 

you may have and air leak as well

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The damaged throttle cable could very well be an explanation to the engine revving at startup. I've seen horrible accidents from a throttle sticking.

 

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I cant tell if i have a air leak bc as soon as start the bike up it revs really high is there another way to check for it other then spraying it wd 40 ? 

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Yea im getting a new cable soon. When i did have it running the bike would ride slowly by its self without me touching it. Which mean the cable is probably being pulled up somewere causing the door to slide up

Edited by Cody_

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Usually when you release the throttle you can hear a loud click from the slide hitting the carb bottom. Do you hear this sound?

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Yea i do hear that sound. 

 

Thats why i didn't think it was getting stuck .  Bc i can hear that sound

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3 minutes ago, Cody_ said:

Were are the crank seals located? 

The crank seals are located in the engine cases behind the clutch on one side and behind the magneto/stator plate on the other side.  If you are lucky you will be able to get them out and replace them with out having to split the center cases.

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1 minute ago, Cody_ said:

Ok thank u sounds like alot of fun 

I was able to do the seals on my 1978 RM 125 without having to split the cases.  Don't ask me how because I don't remember.

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Ok ima do everything else first and try an eliminate things because thats going to be the most difficult so i dont want to change it if i dont have to . 

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1 minute ago, Cody_ said:

Ok ima do everything else first and try an eliminate things because thats going to be the most difficult so i dont want to change it if i dont have to . 

That is the right way to do things.  Easiest first, hardest last.  Let us know what fixes the problem so that the collective can pass it on to the next person with this problem.

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Usually, one tell tale sign of an air leak from the crank seal is some dirt and oil making a trail behind the magneto and flywheel. If you remove the left side cover you can inspect for that and usually you can confirm by spraying some starting fluid around the flywheel and hear the engine revving, but yours is already revving... That's the problem...

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Yea ik thats why i couldnt check for that but ill update everyone when infix the problems 

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If you have leaking crank seals you'll most likely have play in the crank bearing causing seal to wear and suck air/oil .would be temp fix if just replace seal. Feel for up and down play at flywheel and right side drive gear the one in front of clutch 

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If there is play there what all would i have to replace. I also noticed some green coolant in my top engine . Is that supposed to be there ? Im new to dirtbikes so sorry for all these questions 

 

Edited by Cody_

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