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Dirt bike wont start!

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Hello everybody!

I just picked up an 03 yz250 and I have my first problems (my fault). Upon inspecting the air filter, I found that it was probably the original one from 2003. After clearing it out by hand, I put a clean rag in the air box for the time being. I drained out the mystery premix that was left in the tank, and added a gallon of yamalube 32:1. It started right up, and I wanted to clear it out a bit, so I floored it in first gear. Like an idiot, I completely forgot I had stuffed a rag in the airbox. It got sucked all the way in, and suffocated the bike after I floored it. I pulled the airbox, unclogged the rag, and checked the intake side of the carb as well as the reeds. Everything was clear of debris/ rag remains. Now I cannot get her to start. Starter fluid wont work. Fuel poured in the cylinder wont work, and I am baffled. I have spark when kicking it over and grounding it on the case. I even replaced the plug, hoping it had been fouled/flooded when the bike suffocated.
Anybody have any ideas or suggestions? Is there a procedure I could follow to make sure its not flooded/ to drain it?

Thanks in advance

Nate

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You can't ride it when it's on the rag.  :lol:

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If you don't have 100% of the rag then rest is in the motor and you will need to pull the cylinder at a minimum.  If you do have all the rag the reeds could be damaged. Pull the Sparkplug too. If it sucked some lint from the rag you could have fouled a plug.

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Just now, GreenMT_Rider said:

If you don't have 100% of the rag then rest is in the motor and you will need to pull the cylinder at a minimum.  If you do have all the rag the reeds could be damaged. Pull the Sparkplug too. If it sucked some lint from the rag you could have fouled a plug.

Also could have fouled up the carb with bits from the rag.

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I know, huge bonehead move on my part. I have all of the rag, pulled the airbox, carb, reeds, and cleaned all of them with carb cleaner. No lint as far as I can tell. I put a new spark plug in it. How would you diagnose damaged reeds? I think that is the problem. When I pulled the reed assembly out, and pointed it to the sky, I could see some light coming through on one row. Almost seems the carbon fiber/plastic plate is slightly bent. Is that what you mean by damaged reeds? Is there a way to repair that, or is it time for a v force reed upgrade to match my fmf gnarly? :)

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My experience, on two old smokers, has been that if you can see light through the ends of the petal or along the sides then it will not idle as well, be more difficult to start, have a low rpm miss, and the throttle response will not be crisp...but if the gaps are small, it should at least start.

By "damaged", I meant big gaps or pieces of petal missing.

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Well, she's running again but I have no idea what I did right! I disassembled the reed assembly, bent/coaxed the reeds to close the gap, and put in yet another new plug. Now she's alive again. Thanks for all of the help!

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4 minutes ago, Na Bikes said:

Well, she's running again but I have no idea what I did right! I disassembled the reed assembly, bent/coaxed the reeds to close the gap, and put in yet another new plug. Now she's alive again. Thanks for all of the help!

I would recommend new reed petals if that's the case, they aren't too expensive and your bike will run properly.

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Thats what I was planning on doing. It is worth upgrading to vforce or boyesen cage, or should i just get boyesen petals for 50$? They fit oem cage.

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Bike was probably just flooded.  The rag acted as a huge choke at high RPM.  You sucked a bunch of fuel into the motor and it sat in the crankcase. You let it sit for a few hours and it evaporated.  

Just my $0.02.

Doc

 

Edited by Doc_d
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