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YZ250 Throttle Sticking

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So I was doing a hare scramble last weekend, leading up to the race I've had ZERO problems with my '11 YZ250. Part way through the first lap my throttle stuck wide open. Here's the video of it after I got it home (sorry no video of the crash that resulted)

 

https://www.youtube.com/watch?v=56VV0GobMQo

 

I took apart the throttle assembly and there's nothing in there that would hang it up. All is fine on that end. 

 

Took apart the top of the carb and again everything looks fine. It appears that the return spring is not the same spring rate or something I can't see is hanging up. 

 

Feel free to use the schematic to tell me which parts I should replace or clean

 

http://www.rockymountainatvmc.com/oem-schematic/2

 

 

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With your top of your carb disconnected, if you twist the throttle does it still stick? I'm thinking there is either a problem with your throttle cable (fray or bind under the tank somewhere), or your slide is sticking inside the carb. Is there any chrome flaking off the slide?

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With your top of your carb disconnected, if you twist the throttle does it still stick? I'm thinking there is either a problem with your throttle cable (fray or bind under the tank somewhere), or your slide is sticking inside the carb. Is there any chrome flaking off the slide?

It still sticks with the top off. No chrome flakes.

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Ok with the top of the carb off and slide/spring disconnected and the end of the cable out of the throttle assembly I would pull/push it back and forth from either end to see if the cable moves freely. I'm betting that it won't and you have a fray in the cable maybe just above where it goes into the top of the carb.

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ImageUploadedByThumper Talk1402440181.564885.jpg

Well this pisses me off. Turns out it was the damn hand guard that was making it stick. I didn't suspect it because I've got a good 3 hours on the bike since installing them with no issues and didn't change anything before the race. The side mount touching the throttle tube was the issue.

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Ha well at least you found the issue. I usually move my throttle assembly in little so that even when the slop in my throttle tube is pulled out towards the end of the bar, I still have an eighth inch gap before handguard wrap around.

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So now I have a new issue. Put the bike all back together. Turned the gas on, and it is pouring through the carb and right out the drain hoses, from all the drain hoses. All I did to the carb was remove the top cover to inspect te cable. In the process I removed the throttle valve but didn't adjust anything. Do u know what I did? http://youtu.be/UqKdpZmxfL0

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