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Crf450r stroker jetting dilemma

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Ok I am working on a 06 crf450r that just was rebuilt with a cylinder works stroker crank and vertex high comp piston. Before the rebuild the bike had a fmf full exhaust and a boysen acc pump and ran perfectly. Now the bike is super hard to start when hot or cold and when running if u let it idle it will just seem to flame out or die after 2-3sec and it a ***** to start back up again . When running and on the track the bike makes great power and runs smooth but if u kill it or it dies its a ***** to get going again . I dunno of its weak spark or a jetting issue So if anyone can point me in the right direction of whats up with this thing I would appreciate it.

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Have you re-adjusted the fuel screw, and where is it

I have been in and out with that thing and seemed to make little if any difference . Right now its at 1.25 out .

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Those are all typical symptoms of a leaking intake valve, clogged pilot jet passage above the pilot jet, or a weak stator

the head is all new with faction ss valves and I completely went through the carb already. And have new jets also to try . Not sure how to test the stator or the coil ???

I have felt at time a tingle come through the clutch lever like I was getting a small small electrical shock

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I thinkni have the hard starting issue figure out. It seemed thst the coil cap was not all the way into the coil wire. Now it will start better. Now im trying to figure out why when you got mig to wot in 3rd the bike will idle down and die/flame out? Unless you chop the throttle then the idle comes back to normal? Also if you are trying to take off sloo or idel slo the 1st 1/8 throttle thebike will go puhh and die . I went back to the stock jetting specs in the service book .

gotnone trykng to work on it

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Maybe the main idle(air screw) is un screwed i had the same problem on my ktm 250 sxf follow the cable to the main screw and look into it and just screw it back in if that is the problem

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