HELP!!! 07' Electrical? Fuel? Won't run....


7 replies to this topic
  • lftdjeep426

Posted July 01, 2009 - 04:53 PM

#1

HeyGuys..... need some help on this one. My 07' 450 won't run. Last weekend I went to ride and fired up the bike and after about a mile on the trail I was going through some sand whoops in the meat of 4th and it started sputtering and died as soon as I let off the throttle. I brought it home after futile attempts to re-fire it. I changed the plug and nothing. I pulled the carb and cleaned it and put it back in and no fire. I checked the spark and it has good spark. I checked the resistance of all of the electrical system and when I applied some dielectric grese to the connections and buttoned it back up it fired, idled and reved. I shut it off for the night. Today when I got home I put everything back together and kicked it a few times, backfired a couple of times and then fired up. I took it off idle and let it finish warming up reved it a few times (nothing excessive) and I took off down the street. about 1/2 a block it did the same thing, while I was giving it consistant throttle it started sputtering and died. Wouldn't re-fire. I brought it back in and pulled the carb and tried the carb off of my 250f and nothing won't fire. I would think it was a carb issue. I guess it could be electrical but what could it be. I'm at my witts end and have run out of answers. Can you guys help?

Figures, I just took a paycut at work so I REALLY don't want to have to take it to the shop.......

So much for getting a new bike to not have as many problems..... its got 42 hours on it and I put 38 of those on it..... Its basically stillpretty new.....

  • lftdjeep426

Posted July 01, 2009 - 08:14 PM

#2

Any thoughts would be a great help......

  • grayracer513

Posted July 01, 2009 - 08:43 PM

#3

Test for spark. If you have none, or it seems weak, test the stator. If the compression of the engine seems abnormal in any way, check the cam timing.

  • jeffboyd47m

Posted July 01, 2009 - 09:57 PM

#4

Another thing that is worth checking is the spark plug cap coil. I had one go out on my bike and finally figured it out by borrowing the cap from my son's bike. If you know of anyone with a 06-09 the caps are all the same and easy to swap and check.
JB

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  • lftdjeep426

Posted July 02, 2009 - 04:40 AM

#5

can I use the one off of my 06' 250f?

  • lftdjeep426

Posted July 02, 2009 - 05:11 AM

#6

Just came out this morning and it did it again, fired first kick, let it idle for a few minutes and I took off down the street and when I cruised into 5th 1/4 throttle it sputtered and died. Wouldn't start again? I swear this sounds fuel related but I'm pretty sure I ruled that out by trying the other carb. What electrical could be making it do this?

  • usmcpaul

Posted July 02, 2009 - 05:47 AM

#7

Did you check the vent line?

Try this scenario on for size. It started and ran for a while until it created a vacuum in the gas tank. Then you probably took it back and shut the fuel petcock off to change the carb; thus maintaining the vacuum in the tank.

Then you installed the other carb, when you opened the fuel back up, the vacuum was still keeping it from getting fuel.

Just a suggestion, try running it with the fuel cap loose.

  • WB450

Posted July 02, 2009 - 06:59 AM

#8

Do you have a new gas cap? Make your cap vents the tank.





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