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2009 450R won't start....

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Hey guys, lurked and searched the site over the years but have not had a real reason to post till now...

I have a 2009 CRF 450r that I can not to get to start. It ran perfectly this spring, just a little hard to start which sounds typical for an 09. The last time it ran I had a really tough time getting it started, but after it did start it ran perfectly. When I tried to start it again, it just plain wouldn't start and has not ran since. 

I checked the valves and the exhaust was a little loose for some reason so I had them adjusted to make sure they were in spec. 

It has great spark. 

It has great compression.

it has 50lbs of fuel pressure  

the condensor holds 12v

It had a cylinder works 478 bbk and fast head with stage 2 hot cam and a dobeck auto tune programmer. (This is my snowbike in the winter). I unplugged the programmer and no change. 

Is there a way to check if the injector is spraying? Pull it out and kick? 

What else do I need to check? 

 

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I have a very similar setup with my 09 (488 with cylinder works head and stg3 cam) It had similar problems. I had fuel pressure but it ended up being the fuel pump anyway. Take it out and check the injector for crud while you're at it. 

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I did some more diagnosing and my stator is reading 2 ohms, which is one ohm too high....don't know how much difference that would make it I ordered a tt ho stator.....if the bike ever runs again I can put a light at on it anyway.

the fuel pump is in spec for flow and pressure....don't see how it could be the pump? 

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The pumps are notoriously bad, especially the original ones before the redesign. I rebuilt the motor twice looking for the issue, before I replaced the pump. It's worth taking apart and having a look at it. I don't know why they act like that but I'm not the only one to have strange symptoms on an 09 to have it be the pump. 

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Sounds like a classic tight intake valve situation. Check the intake lash. I bet its at .001" or zero. Ive seen them less than zero where the intakes are literally hanging open. Have you tried bump starting it? If it fires, its probably the intake valves. But it sounds like youve got it down already, so just check the lash. .006" on the intakes, .008 on the exhausts. Checking the intake lash is a pain in the ass on the 09 and is easy to get wrong because the cam tower it completely in the way. And make sure the decompressor is actually retracting the pin when the weight moves out.

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