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2003 yz250f wont start

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Hey guys my buddy has yz250f that will not start valves is spec timing spot on, but it is not Gettn fuel spark plug was dry after new plug put in, so I took the plug out squirted some gas in the plug whole and nothing no backfire no ignition nothing, but it is getting a spark... I Dnt get it is there a possibility the spark is too weak??

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take off the subframe witch holds almost half of the bike unscrew the airbox then take a peek on your carb give some throttle if it shoots gas then its getting fuel! while your half way taking off the carb mind as well clean it just in case! goodluck

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The whole bike was just apart carb was off went thru and cleaned jets everything, why would fuel in the cylinder not ignite since it's Gettn spark??? Weak spark?

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Mybe its your stator, that's were the electric coming from check that or replace it.b4 you do that did the bike was running okey b4?

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I guess she said that it was very hard to start, had no power.... Which to me indicated valve clearance so I checked em and they were out so shimmer

It timed and now no fuel Gettn to cylinder manually put fuel in cylinder and nothing no backfire no flame no nothing so idk if it's not Gettn a strong enough spark? I held the plug to the head pipe and kicked it and it is sparking

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You are missing something obvious. All an engine needs to run is fuel, compression and a spark. You claim to have all three yet, it will not run. That is not possible.

At one point the bike did run. Then you 'fixed it' Now it does not run. You stated you re-shimmed the valves, right? Well something you did is not correct.

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this happened to me. i got a new plug and it wasnt sparking enough for some reason and i put a another new one in it ran fine

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Cool buddy I'm gonna try the plug, cuz nothing else makes sense regardless if the timing was off which it's not, you put fuel in the cylinder and add spark you should get something a backfire something

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How much starter fluid did you put in? You put in too much it won't fire. I've always just gave it a quick squirt down the carb throat so it has time to mix with the air

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Took a water bottle put gas in poked a whole in the cap and squirted some in the spark plug whole not alot tho

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