YZ 450 will not start!


15 replies to this topic
  • guitarnut57

Posted March 30, 2009 - 10:02 AM

#1

Ok guys, you have no idea how much I would appreciate your advice on this one. Bike is an 04 YZ 450. Here is a recap of what happened last week:

Last Weekend - Bike ran strong. Washed bike, changed filter, and put it away.

Wednesday - Left bike uncovered during thunderstorm :thumbsup:. It was rained on for about 2 hours before I could get home to cover it.

Saturday - Spent hours getting my bike ready for Sunday. Started the bike to get it warmed up for an oil change. It started, but I noticed that the idle was not as high as it usually was, even after running for about a minute. Didn't think much of it, and went ahead and changed the oil.

Sunday - Got to the track. Bike started and ran for about 20 seconds on choke. As soon as I pushed in the choke button, the bike died. Kicked and kicked and kicked and kicked and kicked and kicked. Even a buddy kicked and kicked and kicked...Kicked for about an hour solid. Nothing. Turned the gas off and drained the carb. Kicked for who knows how long... Nothing.

Please help!

  • mkporn

Posted March 30, 2009 - 10:21 AM

#2

drain all the gas out, pull the hex nut drain on the carb and clean (don't just drain it by loosening the allen screw) put a new plug in it and ride..

  • grayracer513

Posted March 30, 2009 - 10:43 AM

#3

Get some Berryman's B-12 Carb cleaner in a non-aerosol can. If you can't find it, use ethyl alcohol from a drug store. Drain the carb. Fill the carb through the fuel line with either fluid and let it sit there. Drain the tank. Pour a half pint of Ethanol into it and slosh it. Drain that.

Refill the tank with fresh gas. Add 4 oz of alcohol or Berryman's to the tank. Drain the carb again, and try it out.

You probably have water lodged in the pilot and/or main jet. The alcohol (Berryman's B-12 has a high content of alcohol) will absorb it.

  • Jack22

Posted March 30, 2009 - 10:48 AM

#4

This may seem a lil redneck, but I have had success. Get a 4-wheeler and pull start it. Some call it bump starting. Try 2nd or 3rd gear and I'll gurantee if your getting any kind of spark, she will fire. Beat the hell out of kick starting.

I have gotten many bikes to run this way that have been flooded or bad gas. Once you get some heat in the motor, they will run.

Do drain the gas if it has water.

  • mkporn

Posted March 30, 2009 - 11:36 AM

#5

Get some Berryman's B-12 Carb cleaner in a non-aerosol can. If you can't find it, use ethyl alcohol from a drug store. Drain the carb. Fill the carb through the fuel line with either fluid and let it sit there. Drain the tank. Pour a half pint of Ethanol into it and slosh it. Drain that.

Refill the tank with fresh gas. Add 4 oz of alcohol or Berryman's to the tank. Drain the carb again, and try it out.

You probably have water lodged in the pilot and/or main jet. The alcohol (Berryman's B-12 has a high content of alcohol) will absorb it.


Where you finding B-12 these days? Everytime I go looking for it to clean out motors that are sluged up i cant find it....good poo it is..:thumbsup:

  • guitarnut57

Posted March 30, 2009 - 11:37 AM

#6

Good. I hope that is my only problem.

Got a good laugh at the "this may seem a lil redneck" post because I have had to resort to that before. :thumbsup: I will definitely try that if the carb cleaning doesn't help.

I wonder how rain water could have gotten into the carb? I could see how it could from power washing, but not rain. Have you guys heard of that happening before? I will let you guys know how the carb cleaning goes in a few days. Thanks

  • fastkann3

Posted March 30, 2009 - 12:21 PM

#7

doesnt have anything to do with water but that is very typical of a yz motor that needs a valve adjust had an 02 250 f and if it didnt start on no more than the third kick time for a valve check no matter what the temp outside my 07 is the same way and anyone i know this is typical

  • jjj109

Posted March 30, 2009 - 01:28 PM

#8

Ok guys, you have no idea how much I would appreciate your advice on this one. Bike is an 04 YZ 450. Here is a recap of what happened last week:

Last Weekend - Bike ran strong. Washed bike, changed filter, and put it away.

Wednesday - Left bike uncovered during thunderstorm :usa:. It was rained on for about 2 hours before I could get home to cover it.

Saturday - Spent hours getting my bike ready for Sunday. Started the bike to get it warmed up for an oil change. It started, but I noticed that the idle was not as high as it usually was, even after running for about a minute. Didn't think much of it, and went ahead and changed the oil.

Sunday - Got to the track. Bike started and ran for about 20 seconds on choke. As soon as I pushed in the choke button, the bike died. Kicked and kicked and kicked and kicked and kicked and kicked. Even a buddy kicked and kicked and kicked...Kicked for about an hour solid. Nothing. Turned the gas off and drained the carb. Kicked for who knows how long... Nothing.

Please help!

def water in fuel. had this happen b4. I will just pull the tank, drain , clean tank, dry with air, and drain carb. Then when you reinstall tank with fresh fuel, open drain on bottom of carb to make sure fresh fuel goes thru the carb. close up , give her a couple twist of the trottle to prime up , choke , kick starter all the way up, and kick her like you got a pair :thumbsup:

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  • paul_arc

Posted March 30, 2009 - 05:37 PM

#9

check your valves, they may be getting tight

  • rdrata

Posted March 30, 2009 - 07:49 PM

#10

:thumbsup: Better check that YZ steering stem too!!!

  • guitarnut57

Posted April 14, 2009 - 07:28 AM

#11

I thought I would give you guys an update on the bike. The mechanic I took it to cleaned the carb, changed the plug, and it fired right up. So it must have had some water in the carb. He said the compression/valves were fine. :p Thanks Again for all your help!

  • Wiz636

Posted April 14, 2009 - 08:54 AM

#12

I thought I would give you guys an update on the bike. The mechanic I took it to cleaned the carb, changed the plug, and it fired right up. So it must have had some water in the carb. He said the compression/valves were fine. :p Thanks Again for all your help!


Just to recap here for future use, the fact that the bike would run only on the choke is the main clue that would point you to a fuel-starvation problem (i.e., something causing it to be running way too lean like the water-clogged jet) and not indicate that it was a valve adjustment issue.

  • guitarnut57

Posted April 14, 2009 - 09:27 AM

#13

Just to recap here for future use, the fact that the bike would run only on the choke is the main clue that would point you to a fuel-starvation problem (i.e., something causing it to be running way too lean like the water-clogged jet) and not indicate that it was a valve adjustment issue.


I'll keep that in mind. Thanks for the tip!

  • live4speed

Posted April 14, 2009 - 09:47 AM

#14

im thinking bad gas...drain and try again...

  • grayracer513

Posted April 14, 2009 - 10:04 AM

#15

im thinking bad gas...drain and try again...

Amazing.

  • 08YZ450Derek

Posted April 14, 2009 - 10:44 AM

#16

Duh GEORGE.





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