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Popping like timing/jetting issue, but tried everything

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Bike:

2007 CRF450R

Problem:

Bike starts easily with a couple blips and choke on. After 10 seconds it pops thru the exhaust when you RPM up and when RPM's come down and runs like crap. It runs VERY HOT and the Yoshi head pipe gets cherry red. It runs like a lean condition with timing off. When you thottle up it is very responsive, but pop, pop, pop.

What I've done:

Just did piston, rings, cam chain and valve adjustment all torqued to spec. Thoroughly cleaned the carb which has 45 and 172 jets and the screw 2 turns out. Checked, rechecked and checked again the valve timing. We even spun the cam gear 180 degrees to see if the marks were off a bit. All line up perfect either way. There are no issues with the intake rubber, it is clean and in very good condition. The seal inside the carb slide was torn so I replaced it. The accelerator pump diaphram is new too. The spark plug is new and it is dark around the edges but clean in the middle. The TPS doesn't matter if it is plugged in or not, runs the same. Feels like something is advanced too much? Thats my gut. HELP

Gas is fresh, exhaust is tight, the filter is clean and lightly oiled, the coolant is "Engine Ice" and circulates when running. What am I missing?

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JJRace,

Thanks for that link. I had started reading that post the other day and never finished. I wish I had! The metal debris that could be colected in the left case side could have been the problem all along. We had the flywheel off to change the chain and shame on me for not thoroughly cleaning that area!! I will give it a try and post my results. Any other ideas would be great too.

Rotordawg

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I cleaned it all up and didn't make a difference. This is very frustrating. I am going to try swapping the carb with another bike and start a process of elimination. Maybe there is a short?

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I figured it out!!!!!

I put the slide plate in upside down after replacing the seal. It will fit either way and I made a mistake.

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I figured it out!!!!!

I put the slide plate in upside down after replacing the seal. It will fit either way and I made a mistake.

As soon as I went through your list of what you'd done I started laughing and knew exactly what it was.

Now, regarding all that crap on the stator...

Where did iron debris come from? What part of your engine is iron? And why is it producing debris?

Very ugly and scary questions... :banana:

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I would say that there has to be some wear that could collect on magnetic parts that may or may not have passed thru the filter or never got to it. I was hoping that was the problem. This picture is after wiping my finger inside the flywheel. We had just done the topend and had only run the motor maybe half hour tops (off and on for couple days) while trying to figure out the carb issue.:banana: The filter is new and we had cleaned the flywheel, but never touched the stator. It is very clean now. There were no chunks, just "metal dust". If they were bigger it may be a problem. For now, the motor is tight, top and bottom, I'm not concerned. I am relieved:banana:

MetalCRF.jpg

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