07 450 carburetor Problems


7 replies to this topic
  • YamieRider411

Posted July 06, 2007 - 06:56 AM

#1

I’m having a little problem with my carburetor. Every now and then when I go to crack the bike the over flow hoses start dump gas out. Not just one but all the hoses. I’m running the new VP U4.1 gas and I put in a JD Jetting kit a while ago. I took the carb apart to see if it was gummed up but it looks pretty good. I cleaned it and that seems to keep it from doing it for awhile. I’ve got a sneaky suspicion it’s the floats. Anyone have this problem?

  • FLjoyride

Posted July 06, 2007 - 07:17 AM

#2

probably the float valve. Take off the float bowl and remove the floats. Look at the valve seat (rubber on the tip of the square needle) and make sure there is no wear (a ring around the rubber section). run the tip of your finger on it too making sure not to scratch it with your fingernail to make sure it is perfectly flat with no scratches or indentations. It could also have something stuck in there temporarily lodging the valve open so make sure you clean it good before you put it back together.

  • Ga426owner

Posted July 06, 2007 - 10:38 AM

#3

I’m having a little problem with my carburetor. Every now and then when I go to crack the bike the over flow hoses start dump gas out. Not just one but all the hoses. I’m running the new VP U4.1 gas and I put in a JD Jetting kit a while ago. I took the carb apart to see if it was gummed up but it looks pretty good. I cleaned it and that seems to keep it from doing it for awhile. I’ve got a sneaky suspicion it’s the floats. Anyone have this problem?


Fellow Georgia Boy,Call VP, all U4 4.1 has been recalled due to engines blowing up....it is replaced with U4.2........do not use this 4.1 fuel at all. Dave Harris is aware of this - if you bought this from him or his dealers.
Your carb is gummed up - floats and in places you can not see. I had the same issue on my 06 - I completely disassembled my carb to get it right....a real mess. I suggest you send your carb to ZipTy for a complete cleaning and their carb mod....you will be amazed at how it will run after this.
Regardless of what you do....do not use that fuel at all. Call VP if you don't believe me.....

  • YamieRider411

Posted July 09, 2007 - 09:04 AM

#4

This is the first I'm hearing about this... Thanks for the FYI. You'd think that VP would issue a news clip. I just call VPs Tech help. He says they are still making it but I should drain it out of my bike. Wow... I thought that the new U4.1 wouldn't gum up the carb... Weren't they advertising that this new fuel would solve that problem? Think I'm going to look for old U4. At least I knew what I was dealing with. By the way, the new 4.1 turned my clear plastic hose on my gas tank brown. Guess I should have known it would do the same to carb. Thanks.

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  • warrior86

Posted July 09, 2007 - 09:38 AM

#5

ga426.....what exactly is their carb mod? im unaware one existed...atleast not of one that i would send my carb out.

  • grayracer513

Posted July 09, 2007 - 09:44 AM

#6

ga426.....what exactly is their carb mod? im unaware one existed...atleast not of one that i would send my carb out.

The emulsion tube is changed, and the air bleeds in the main circuit modified, along with the AP mod.

http://www.thumperta...ad.php?t=458476

  • Ga426owner

Posted July 10, 2007 - 05:19 AM

#7

This is the first I'm hearing about this... Thanks for the FYI. You'd think that VP would issue a news clip. I just call VPs Tech help. He says they are still making it but I should drain it out of my bike. Wow... I thought that the new U4.1 wouldn't gum up the carb... Weren't they advertising that this new fuel would solve that problem? Think I'm going to look for old U4. At least I knew what I was dealing with. By the way, the new 4.1 turned my clear plastic hose on my gas tank brown. Guess I should have known it would do the same to carb. Thanks.


U4.2 is the way to go.....I am testing it and so has Eddie S over on the jetting side. No residue, and great power. Jetting is required...but I found the same to optimize U4. 1 to 2 jet sizes.
U4 ruined my day even after draining it....each and every time.....gummed my carb up very bad on both my bikes...I will never use that again.

  • Ga426owner

Posted July 10, 2007 - 05:21 AM

#8

ga426.....what exactly is their carb mod? im unaware one existed...atleast not of one that i would send my carb out.


Grey gave you the TT link - but ZipTy Racing as well as Tokyo Mods will do this for you.:thumbsup:
My results are spectacular from ZipTy:thumbsup:





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