EXC200 Carb problems

[crfx250]

I've just bought myself an EXC200 2008 model, first two stroke for a long time and it's not going great so far!

 

Started it up and it took a good few kicks to get going and when it did it ran fine for about 5 seconds then just  it just revved right up on it's own, full revs and took the a while to shut it off on the kill switch.

 

So I took the carb out and cleaned everything up. It would only bump start and then it just wouldn't rev out properly at all. So I took the carb apart again, cleaned it, started it up and it started screaming full revs again. 

 

I drained the tank and put different fuel in, new spark plug and checked for air leaks and can't find any. So I'm thinking it's the float valve jamming up but i'm not sure, could the float valve sticking cause the bike to rev out? Before i cleaned the carb the 2nd time I noticed that fuel was draining out of the carb when i had the fuel tap on, when I cleaned it for the last time tonight I couldn't get any fuel in the carb so I guess it's either stuck open or closed.

 

Will a new float valve sort the problem? And I'm wondering about checking the float level if anyone has any idea how to do that? Thanks ?

[facethenorth]

If it revs right up on its own it may have something to do with your slide. Make sure it's not stuck wide oped.

I rebuilt an old rm80 and had the same problem, took me a while to realize the slide was wide open.