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YFZ 450 wont run

Old Oct 1, 2006 | 10:27 PM
  #11  
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Default YFZ 450 wont run

Check your compression first, you may have an intake valve varnish from stale fuel sticking.
 
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Old Oct 2, 2006 | 12:48 AM
  #12  
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Default YFZ 450 wont run

well obviously it has something to do with either the carb or the intake so look over it carefully making sure everything is fine and if you go getting a new carb why not just get aftermarket
 
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Old Oct 5, 2006 | 02:37 PM
  #13  
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Default YFZ 450 wont run

Originally posted by: URCRAZY
Does the motor suck the fuel from the carb, or does the carb shoot the fuel into the motor?
The engine must draw the fuel from the carburetor using vacuum. The only way fuel "shoots" is by way of the accellerator pump.


Originally posted by: URCRAZY
We went through the jets, put different ones in for the air box and K&N.
If you removed the carburetor's slide valve when changing the jet needle, it's very possible you reinstalled the slide valve incorrectly. I don't know how this can happen, but it's happened to quite a few people up to this point.

 
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Old Oct 5, 2006 | 07:50 PM
  #14  
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Default YFZ 450 wont run

No we did not take those ones out. It is comming down to checking the compression, which we will do this weekend, and if we have good compression, its the carb all gummed up somewhere.

Stock compression???Anybody??? around 180 lbs???
 
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Old Oct 6, 2006 | 10:28 AM
  #15  
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Default YFZ 450 wont run

Originally posted by: URCRAZY
No we did not take those ones out. It is comming down to checking the compression, which we will do this weekend, and if we have good compression, its the carb all gummed up somewhere.

Stock compression???Anybody??? around 180 lbs???
It will be hard to check the compression with the auto decompression pin on the cam.
Also if there is fuel coming out of the over flow's on the top of the carb the float is stuck open...
also it is probaly dumping fuel into the motor and not letting it fire becasue of all the fuel in the motor...
Check the float in the carb and make sure it is closing all the way....
let me know become's of it....

bobby
 
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Old Oct 6, 2006 | 12:28 PM
  #16  
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Default YFZ 450 wont run

Check your petcock, lol
That really could be part of the prob..some simple things can be a pain...My rappy was dieing like that..and it ended up being the gas cap hole was pluged..Not leting air in so the gas could go into the carb..
 
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